Question:

What command cancels star 72?

Answer:

*72 Lets you automatically send incoming calls to another number, including pagers and mobile phones. The code to disable this feature is *73.

More Info:


Pager
A pager is a wireless telecommunications device that receives and displays numeric or text messages, or receives and announces voice messages. One-way pagers can only receive messages, while response pagers and two-way pagers can also acknowledge, reply to, and originate messages using an internal transmitter. Pagers operate as part of a paging system which includes one or more fixed transmitters (or in the case of response pagers and two-way pagers, one or more base stations), as well as a number of pagers carried by mobile users. These systems can range from a restaurant system with a single low-power transmitter, to a nationwide system with thousands of high-power base stations. One of the first practical paging services was launched in 1950 for physicians in the New York City area. Physicians paid US$12 per month for the service and carried a (6 oz) pager that would receive phone messages within (25 mi) of a single transmitter tower. The system was manufactured by the Reevesound Company and operated by Telanswerphone. In 1960, John Francis Mitchell combined elements of Motorola's Walkie Talkie and automobile radio technologies to create the first transistorized pager, and from this point, paging technology continued to advance, and pager adoption continued to expand, until the early 1990s. However, by the mid-1990s, as cellular technologies became cheaper and more widely available, advanced services began to displace paging as a commercial product. Today, pagers exist largely as niche products, finding preferential use in applications such as hospitals, public safety, and retail locations where their simplicity, high reliability, and low cost represent significant advantages. Paging systems are operated by commercial carriers, often as a subscription service, and they are also operated directly by end users as private systems. Commercial carrier systems tend to cover a larger geographical area than private systems, while private systems tend to cover their limited area more thoroughly and deliver messages faster than commercial systems. In all systems, clients send messages to pagers, an activity commonly referred to as paging (e.g., "I just paged Doctor Watson"). System operators often assign unique phone numbers or email addresses to pagers (and pre-defined groups of pagers), enabling clients to page by telephone call, e-mail, and SMS. Paging systems also support various types of direct connection protocols, which sacrifice global addressing and accessibility for a dedicated communications link. Automated monitoring and escalation software clients, often used in hospitals, IT departments, and alarm companies, tend to prefer direct connections because of the increased reliability. Small paging systems, such as those used in restaurant and retail establishments, often integrate a keyboard and paging system into s single box, reducing both cost and complexity. Paging systems support several popular direct connection protocols, including TAP, TNPP, SNPP, and WCTP, as well as proprietary modem- and socket-based protocols. Additionally, organizations often integrate paging systems with their Voice-mail and PBX systems, conceptually attaching pagers to a telephone extensions, and they set up web portals to integrate pagers into other parts of their enterprise. A paging system alerts a pager (or group of pagers) by transmitting information over an RF channel, including an address and message information. This information is formatted using a paging protocol, such as 2-tone, 5/6-tone, Golay, POCSAG, FLEX, ERMES, or NTT. Two-way pagers and response pagers typically use the ReFLEX protocol. Pagers themselves vary from very cheap and simple beepers, to more complex personal communications equipment, falling into eight main categories: Modern paging systems typically use multiple base transmitters to modulate the same signal on the same RF channel, a design approach called simulcast. This type of design enables pagers to select the strongest signal from several candidate transmitters using FM capture, thereby improving overall system performance. Simulcast systems often use satellite to distribute identical information to multiple transmitters, and GPS at each transmitter to precisely time its modulation relative to other transmitters. The coverage overlap, combined with use of satellite communications, can make paging systems more reliable than terrestrial based cellular networks in some cases, including during natural and man-made disaster. This resilience has led public safety agencies to adopt pagers over cellular and other commercial services for critical messaging. Pagers are still in use today in places where mobile phones typically cannot reach users, and also in places where the operation of the radio transmitters contained in mobile phones is problematic or prohibited. One such type of location is a large hospital complex, where cellular coverage is often weak or nonexistent, where radio transmitters are thought to interfere with sensitive medical equipment and where there is a greater need of assurance for a timely delivery of a message. Another is a facility handling classified information, where various radio transmitter or data storage devices are excluded to ensure security. A terrorist incident in London in 2005 was accompanied by overload and subsequent failure of SMS systems during the inevitable panic use by the general public, and showed that pagers, with their absence of necessity to transmit an acknowledgement before showing the message, and the related capability to operate on very low signal levels. Restaurant pagers are in wide use today. These are generally from the beeper category. Customers are given a portable receiver that usually vibrates, flashes, or beeps when a table becomes free or when their meal is ready. Pagers have been popular with birdwatchers in Britain and Ireland since 1991, with companies Rare Bird Alert and Birdnet Information offering news of rare birds sent to pagers that they sell. The U.S. paging industry generated $2.1 billion in revenue in 2008, down from $6.2 billion in 2003. In 1962 the Bell System—the U.S. telephone monopoly affectionately known as "Ma Bell"—presented its Bellboy radio paging system at the Seattle World's Fair. Bellboy was the first commercial system for personal paging. It also marked one of the first consumer applications of the transistor (invented by Bell Labs in 1947), for which three Bell Labs inventors received a Nobel Prize in Physics in 1956. Solid-state circuitry enabled the Bellboy pager, about the size of a small TV remote device, to fit into a customer's pocket or purse, quite a feat at that time. The Bellboy is a terminal that notifies the user when someone is trying to call. When the person receives an audible signal (a buzz) on the pager, he finds a telephone and calls the service center, which informs him of the caller's message. As is the case with many new technologies, the functionality of the pager shifted from necessary professional use to a social tool integrated in one's personal life. Within a short time span, pagers evolved from a tool for "technocratic elites" to a tool used by "kids living in the projects". During the rise of the pager, it became the subject of various forms of media; most notably in the 1990s hip-hop scene. Upcoming mainstream artists such as Ice Cube, Method Man, and A Tribe Called Quest began referencing forthcoming mobile technologies, in particular the pager. A Tribe Called Quest's single 'Skypager' directly speaks of the importance of such a wireless communication device. Q-Tip conveys that the skypager "serves an important communicative function for a young professional with a full calendar". Three 6 Mafia's "2-Way Freak" and the smash hit "Bug a Boo" from Destiny's Child also make reference to pagers. Pagers were a featured segment on the 1991 episode I Love the '90s: Part Deux. The segment explored the device's entrance into mainstream pop culture; it also discussed the humorous use of calculator spelling to send messages through the devices. The growing popularity of cellphones in the early 21st century was accompanied by a corresponding decline in pager use by the general population. This shift accounts for Sam Flynn's amusement when Alan Bradley says "I was paged last night" in Tron: Legacy. Likewise, the 30 Rock sitcom character Dennis Duffy attracts disdain and mockery for his career as a pager salesman. The use of pagers by the Barksdale crew of drug dealers in Baltimore features prominently in the first season of the HBO series The Wire. Pagers also have privacy advantages compared with cellular phones. Since a one-way pager is a passive receiver only (it sends no information back to the base station), its location cannot be tracked. However, this can also be disadvantageous, as a message sent to a pager must be broadcast from every paging transmitter in the pager's service area. Thus, if a pager has nationwide service, a message sent to it could be intercepted by criminals or law enforcement agencies anywhere within the nationwide service area. Many paging network operators now allow numeric and textual pages to be submitted to the paging networks via email. This is convenient for many users, due to the widespread adoption of email; but email-based message submission methods do not usually provide any way to ensure that messages have been received by the paging network. This can result in pager messages being delayed or lost. Older forms of message submission using the Telelocator Alphanumeric Protocol involve modem connections directly to a paging network, and are less subject to these delays. For this reason, older forms of message submission retain their usefulness for disseminating highly-important alerts to users such as emergency services personnel. Common paging protocols include TAP, FLEX, ReFLEX, POCSAG, Golay, ERMES and NTT. Past paging protocols include Two-tone and 5/6-tone. In the United States, pagers typically receive signals using the FLEX protocol in the 900 MHz band. Commercial paging transmitters typically radiate 1000 watts of effective power, resulting in a much wider coverage area per tower than a mobile phone transmitter, which typically radiates around 0.6 Watts per channel. Although FLEX paging networks tend to have stronger in-building coverage than mobile phone networks, commercial paging service providers will work with large institutions to install repeater equipment in the event that service is not available in needed areas of the subscribing institution's buildings. This is especially critical in hospital settings where emergency staff must be able to reliably receive pages in order to respond to patient needs. Unlike mobile phones, most one-way pagers do not display any information about whether a signal is being received or about the strength of the received signal. Since one-way pagers do not contain transmitters, one-way paging networks have no way to track whether a message has been successfully delivered to a pager. Because of this, if a one-way pager is turned off or is not receiving a usable signal at the time a message is transmitted, the message will not be received and the sender of the message will not be notified of this fact. In the mid-1990s, some paging companies began offering a service, which allowed a customer to call their pager-number, and have numeric messages read back to them. This was useful for times when the pager was off or out of the coverage area, as it would know what pages were sent to you even if you never actually received the page. Other radio bands used for pagers include the 400 MHz band, the VHF band, and the FM commercial broadcast band (88-108 MHz). Other paging protocols used in the VHF, 400 MHz UHF, and 900 MHz bands include POCSAG and ERMES. Pagers using the commercial FM band receive a subcarrier, called the Subsidiary Communications Authority, of a broadcast station. On-site paging systems in hospitals, unlike wide area paging systems, are local area services. Hospitals commonly use on-site paging for communication with staff and increasingly for contacting waiting patients when their appointment is due. These offer waiting patients the opportunity to leave the waiting area, but still be contacted.

Caller ID
Caller ID (caller identification, CID), also called calling line identification (CLID), calling number delivery (CND), calling number identification (CNID) or calling line identification presentation (CLIP), is a telephone service, available in analog and digital phone systems and most voice over Internet Protocol (VoIP) applications, that transmits a caller's number to the called party's telephone equipment during the ringing signal, or when the call is being set up but before the call is answered. Where available, caller ID can also provide a name associated with the calling telephone number. The information made available to the called party may be displayed on a telephone's display, on a separately attached device, or be processed by an attached computer with appropriate interface hardware. Caller ID may be used to display a caller's telephone number (and, in association with a database, the caller's name) on a called user's telephone, computer or television screen. This works in most countries; although systems are incompatible, each country will have appropriate equipment. A modem can pass CLID information to a computer for purposes of call logging or blocking, but this can be problematic as modems in different countries have different systems, causing hardware or software incompatibilities. However, many modems are designed and programmed to handle multiple signalling methods, and can be configured to use the local standard. Caller ID may be used to track down or limit the impact of telemarketers, prank calls, and other annoyances. However, it can also impede communication by enabling users to become evasive. The concept behind caller ID is the value of informed consent; however, it also poses problems for personal privacy. Another problem is that the possibility of caller ID spoofing makes it unreliable. In some countries, the terms caller display, calling line identification presentation (CLIP), call capture, or just calling line identity are used; call display is the predominant marketing name used in Canada (although some customers use the phrase caller ID). The idea of CNID as a service for POTS subscribers originated from automatic number identification (ANI) as a part of toll free number service in the United States. However, CNID and ANI are not the same thing. ANI was originally a term given to a system that identified a caller placing a long distance call, in a non-electronic central office switch. Previous to this implementation, after dialling the long distance number, the caller would be intercepted by the operator to request their number before the call proceeded. Caller ID is made up of two separate pieces of information: the calling number and the billing (or subscriber) name where available. When a call is made from a given name, this name can be passed on through a number of different methods. For example, the caller's name may be datafilled in the originating switch, in which case it is sent along with the number. More commonly, a database is accessed by the receiving switch, in order to match the number to a name. If the name does not exist, then the city, State, Province, or other designation may be sent. Some of these databases may be shared among several companies, each paying every time a name is "extracted" It is for this reason that mobile phone callers appear as WIRELESS CALLER, or the location where the phone number is registered (these vary based on which company owns the block of numbers, not the provider to which a number may have been ported). Additionally, nothing ensures that the number sent by a switch is the actual number where the call originated; the telephone switch initiating the call may send any digit string desired as caller ID. As such, the telephone switch, and therefore the operating entity, must also be trusted to provide secure authentication. The displayed caller ID also depends on the equipment originating the call. If the call originates on a POTS line (a standard loop start line), then caller ID is provided by the service provider's local switch. Since the network does not connect the caller to the callee until the phone is answered, generally the caller ID signal cannot be altered by the caller. Most service providers however, allow the caller to block caller ID presentation through the vertical service code *67. A call placed behind a private branch exchange (PBX) has more options. In the typical telephony environment, a PBX connects to the local service provider through Primary Rate Interface (PRI) trunks. Generally, although not absolutely, the service provider simply passes whatever calling line ID appears on those PRI access trunks transparently across the Public Switched Telephone Network (PSTN). This opens up the opportunity for the PBX administrator to program whatever number they choose in their external phone number fields. Some IP phone services (ITSPs, or Internet Telephony Service Providers) support PSTN gateway installations throughout the world. These gateways egress calls to the local calling area, thus avoiding long distance toll charges. ITSPs also allow a local user to have a number located in a "foreign" exchange; the New York caller could have a Los Angeles number, for example. When that user places a call, the calling line ID would be that of a Los Angeles number, although they are actually located in New York. This allows a call return without having to incur long distance calling charges. With cellphones, the biggest issue appears to be in the passing of calling line ID information through the network. Cellphone companies must support interconnecting trunks to a significant number of Wireline and PSTN access carriers. In order to save money, it appears that many cellphone carriers do not purchase the North American feature Group D or PRI trunks, or SS7 trunks required to pass calling line ID information across the network.][ In 1968, Theodore George “Ted” Paraskevakos, while working in Athens, Greece as a communications engineer for SITA, began developing a system to automatically identify a telephone caller to a call recipient. After several attempts and experiments, he developed the method in which the caller's number is transmitted to the called receiver's device. This method was the basis for modern-day Caller ID technology. From 1969 through 1975, Paraskevakos was issued 20 separate patents related to automatic telephone line identification, and since they significantly predated all other similar patents,][ they appear as prior art in later United States Patents issued to Kazuo Hashimoto and Carolyn A. Doughty. In 1971, Paraskevakos, working with Boeing in Huntsville, Alabama, constructed and reduced to practice a transmitter and receiver, representing the world's first prototypes of caller-identification devices. They were installed at Peoples' Telephone Company in Leesburg, Alabama and were demonstrated to several telephone companies with great success. These original and historic working models are still in the possession of Paraskevakos. In the patents related to these devices, Paraskevakos also proposed to send alphanumeric information to the receiving apparatus, such as the caller's name, and also to make feasible banking by telephone. He also proposed to identify the calling telephone by special code (e.g., "PF" for public phone, "HO" for home phone, "OF" for office phone, "PL" for police). In May 1976, Kazuo Hashimoto, a prolific Japanese inventor with over 1000 patents worldwide, first built a prototype of a caller ID display device that could receive caller ID information. His work on caller ID devices and early prototypes was received in the Smithsonian Institution, National Museum of American History in 2000. U.S. patent 4,242,539, filed originally on May 8, 1976, and a resulting patent re-examined at the patent office by AT&T, was successfully licensed to most of the major telecommunications and computer companies in the world. Initially, the operating telephone companies wanted to have the caller ID function performed by the central office as a voice announcement and charged on a per-call basis. John Harris, an employee of Northern Telecom's telephone set manufacturing division in London, Ontario promoted the idea of having caller ID as a telephone set display. The telephone was coded ECCS for Enhanced Custom Calling Services. A video of his prototype was used to leverage the feature from the central office to the telephone set. Early in 1977 Nélio Nicolai, a Brazilian inventor, created a machine capable of identifying and displaying the caller ID, he named it BINA (B identifies number of A or Binary Identifies Number Address). He patented the invention, but lack of support from the Brazilian patent-issuer authority INPI made him pursue the judicial system to effectively collect the royalties from his invention (the lawsuit is still running). He received many proposals to drop his wish for a full patent recognition, but did not accept any. The first commercially available BINAs appeared in 1982 in the Brazilian capital, Brasília. In 1996, Nélio received the WIPO (World Intellectual Property Organization) award for his invention. There is an ongoing debate on how Bell Canada approached Nélio and its former employer (Telebrasília) in the mid-80s asking for technical papers and prototypes (Nélio travelled to Canada). Experimental use of the system happened at the Canadian city of Peterborough, Ontario. Talks ceased and surprisingly, in 1986, Bell Canada announced such tests to the general public, with following commercialization starting in 1988. Nélio says that no royalties were ever collected. The first market trial for Caller ID and other "Custom Local Area Signaling Services" was conducted by BellSouth as one of the "TouchStar" services on July 7, 1984 in Orlando, Florida. The Lines of Business (marketing) department in BellSouth Services named the service "Caller ID". The other Regional Bell Operating Companies later adopted the name and eventually became the generally accepted name in the US. Planning for the trial was initiated by a team in Bell Laboratories, AT&T Corporation, and Western Electric before the Bell System divestiture, with the participation of Southern Bell. The purpose of these trials was to assess the revenue potential of services that depend on deployment of the common channel signaling network needed to transmit the calling number between originating and terminating central offices. Trial results were analyzed by Bellcore members of the original team. In 1987, Bell Atlantic (now Verizon Communications) conducted another market trial in Hudson County, New Jersey, which was followed by limited deployment. BellSouth was the first company to deploy caller ID in December 1988 in Memphis, Tennessee, with a full deployment to its nine-state region over the next four years. Bell Atlantic was the second local telephone company to deploy Caller ID in New Jersey's Hudson County. US West Communications (now Qwest/CenturyLink) was the third local telephone company to offer caller ID service in 1989. In 1995, Bellcore released another type of modulation, similar to Bell 202, in which it became possible to transmit caller ID information and even provide call-disposition options while the user was already on the telephone. This service became known in some markets as call waiting ID, or (when it was combined with call-disposition options), Call Waiting Deluxe; it is technically referred to as Analog Display Services Interface. "Call Waiting Deluxe" is the Bellcore (now Telcordia Technologies) term for Type II caller ID with Disposition Options. This CLASS-based POTS-telephone calling feature works by combining the services of call waiting with caller ID but also introduces an "options" feature that, in conjunction with certain screen-based telephones, or other capable equipment, gives a telephone user the option to In the United States, caller ID information is sent to the called party by the telephone switch as an analogue data stream (similar to data passed between two modems), using Bell 202 modulation between the first and second rings, while the telephone unit is still on hook. If the telephone call is answered too quickly after the first ring, caller ID information will not be transmitted to the recipient. There are two types of caller ID, number only and name+number. Number-only caller ID is called Single Data Message Format (SDMF), which provides the caller's telephone number, the date and time of the call. Name+number caller ID is called Multiple Data Message Format (MDMF), which in addition to the information provided by SDMF format, can also provide the directory listed name for the particular number. Caller ID readers which are compatible with MDMF can also read the simpler SDMF format, but an SDMF caller ID reader will not recognize an MDMF data stream, and will act as if there is no caller ID information present, e.g. as if the line is not equipped for caller ID. Instead of sending the caller ID in between the first and second ring, some systems use a "line reversal" to announce the caller ID, or caller ID signals are simply sent without any announcement. Instead of Bell 202, the European alternative V.23 is sometimes used, (without the 75-baud reverse channel) or the data is sent using DTMF signalling. In general, CID as transmitted from the origin of the call is only the calling party's 10-digit phone number. The calling party name is added by the consumer's terminating central office if the consumer has subscribed to that service. Calling name delivery is not automatic. An SS7 (or Signalling System 7) TCAP query may be launched by the called party's central office, in order to retrieve the information for Calling Name delivery to the caller ID equipment at the consumer's location, if the caller's name has not already been associated with the calling party's line at the originating central office. Canadian systems using CCS7 automatically (but not in all cases) send the calling name with the call set-up and routing information at the time of the call. To look up the name associated with a phone number, the carrier in some instances has to access that information from a third-party database, and some database providers charge a small][ fee for each access to such databases. To avoid such charges, some carriers will report the name as "unavailable", or will report the name as "(city), (state)" based on the phone number, particularly for wireless callers. For 800 numbers, they may report a string such as TOLLFREE NUMBER if the name is not available in a database. Telemarketing organisations often spoof caller ID. In some instances, this is done to provide a "central number" for consumers to call back, such as an 800 number, rather than having consumers call back the outbound call centre where the call actually originated. However, some telemarketers block or fraudulently spoof caller ID to prevent being traced. It is against United States federal law for telemarketers to block or to send false caller ID. Individuals can bring civil suits and the Federal Communications Commission (FCC) can fine companies or individuals that are illegally spoofing or blocking their caller ID.][ Some telemarketers have used caller ID itself for marketing, such as by using a toll-free number and registering the text string "FREE MONEY" or "FREE PLANE TICKETS" as the name to be displayed on the caller ID.][ Some Internet service providers (ISPs) providing dial-up access require the customer to use CNID to prevent abuse of the account by unauthorised callers.][ Some systems with dial-up access can be programmed only to accept calls with specific caller ID strings. Most mobile phone providers used the caller ID to automatically connect to voice mail when a call to the voice mail number was made from the associated mobile phone number, bypassing the need to enter a password. While this was convenient for many users, because of spoofing, this practice has been replaced by more secure authentication by many carriers. Different countries often use different standards for transmitting caller ID information. As a result, phones purchased in one country may not be compatible with the local caller ID standard when the phone is used in a different country. For example, the US uses Bellcore FSK, whereas Taiwan uses ETSI FSK, so a phone purchased in the US will not understand Taiwan's caller ID standard. There are even cases where individual state/provinces will use different protocols within a country. There do exist, however, caller ID converters that will translate from one standard to another. Below is a list of countries and the caller ID standard used: Telephone equipment usually displays CLID information with no difficulty. Modems are notoriously problematic; very few modems support the British Telecom standard in hardware; drivers for those that do often have errors that prevent CLID information from being recognised. Other UK telephone companies use slight variations on the Bellcore standard, and CLID support is "hit and miss". In the United States, telemarketers are required to transmit caller ID. This requirement went into effect on January 29, 2004. Courts have ruled that caller ID is admissible. Providers are required by FCC rules to offer "per-call" blocking of caller ID to their customers. Legislation in the United States in 2007[update] would make it illegal to "spoof" caller ID for fraudulent purposes. See caller ID spoofing. Blocking is the common term for preventing the display of a calling number. Telecommunications regulators vary in their requirements for the use and effectiveness of assorted technologies to prevent numbers from being displayed. Generally, unlisted numbers are always blocked. Non-published and regular listed numbers are not usually blocked. But there is varying treatment for the determination of call display blocking because of many factors. If desired, customers should inquire carefully to make sure their number will not be displayed. The telephone service provider may also have vertical service codes which can be dialed to configure blocking as active for all calls or on a call-by-call basis. In some locations in the United States, regulations allow (or require) blocking to be automatic and transparent to the caller. Where blocking is applied on a call-by-call basis (that is, at the time a call is made), subscribers can block their caller ID by dialing a special code (a vertical service code, or VSC) before making a call. In North America and some other regions, the code is *67, while in the United Kingdom and Ireland, it is 141. This special code does not block the information from companies using call capture technology. This means that equipment with caller ID will simply display the word "PRIVATE" or "WITHHELD". When CNID is blocked at the caller's request, the number is actually transmitted through the entire telephone network, with the "presentation withheld" flag set; the destination CO is expected to honor this flag, but sometimes does not—especially when the destination phone number is served by an ISDN PRI. Alternatively, in cases where caller ID is being blocked automatically, it can only be released on a call-by-call basis by dialing a special code (*82 in North America; 1470 in the UK). See "Enabling", below. Similarly, some countries offer anonymous caller rejection, which rejects all calls when the subscriber's number is blocked. Some telephone companies protect their clients from receiving blocked information by routing anonymous calls to a service, where the caller is required to announce himself or herself. The service then asks the called party if they want to accept or reject the call. Other telephone companies play a recording to the caller advising them of the called party's rejection configuration, and often offer advice (such as prefixing their dialing with *82) on how to get their call to the intended called party. Blocking the number is referred to as calling line identification restriction (CLIR). Emergency services will most likely be able to show the restricted number using a service called calling line identification restriction override (CLIRO), or by using general ANI services. These features create a cat-and-mouse game type of situation, whereby subscribers must purchase additional services in order to cancel out other services. Caller ID is a simple string of data that can be read and generated very simply by small computer programs and even some inexpensive devices. Although the caller ID information is transmitted in between the first and second rings, before the phone call is connected, it is possible to mislead the phone company as to the origin of the call, thus defeating caller ID. Although misleading the phone company by generating Automatic Number Identification (ANI) code or by other electronic means is very complex, simpler means do exist. Using services like Vonage or Skype, calling from a pay phone, or using a calling card are easy means to fool Caller ID. Services like Operator One and Rebtel use Caller ID replacement to get around international call charges for missed calls that are returned by the dialed-up party. Since most carriers charge their customers on the basis of caller ID, some VoIP providers use Caller ID replacement to save local plan minutes. In addition, ISDN (PRI) based PBXs (in many cases) can send whatever number(s) they wish to be displayed at the called party's end. This may be their main switchboard number, or the dial-able (DID) extension number that placed the outgoing call. Prefixing the following numbers will disable Caller ID on a call-by-call basis: Other countries and networks vary, however on GSM mobile networks, callers may dial #31# before the number they wish to call to disable it. Depending on the operator and country, there are a number of prefix codes that can unblock Caller ID. On GSM mobile networks, callers may dial *31# before the number they wish to call to enable caller ID.

Landline
A landline telephone (also known as land line, land-line, main line, homephone, landline, fixed-line, and wireline) refers to a phone which uses a solid medium telephone line such as a metal wire or fiber optic cable for transmission as distinguished from a mobile cellular line which uses radio waves for transmission. In 2003, the CIA reported approximately 1.263 billion main telephone lines worldwide. China had more than any other country at 350 million and the United States was second with 268 million. The United Kingdom has 23.7 million residential fixed landlines. In 2008, the world had 1.27 billion fixed line subscribers. A fixed phone line (a line that is not a mobile phone line) can be hard-wired or cordless. Fixed wireless refers to the operation of wireless devices or systems in fixed locations such as homes. Fixed wireless devices usually derive their electrical power from the utility mains electricity, unlike mobile wireless or portable wireless which tend to be battery-powered. Although mobile and portable systems can be used in fixed locations, efficiency and bandwidth are compromised compared with fixed systems. Mobile or portable, battery-powered wireless systems can be used as emergency backups for fixed systems in case of a power blackout or natural disaster. The term landline is also used to describe a connection between two or more points that consists of a dedicated physical cable, as opposed to an always-available private link that is actually implemented as a circuit in a wired switched system (usually the public switched telephone network). So-called leased lines are invariably of the latter type; the implications of a land line in this context are security and survivability. For example, a military headquarters might be linked to front-line units "by landline" to ensure that communication remains possible even if the conventional telephone network is damaged or destroyed. Another example of this is in airports. All air traffic control towers have dedicated lines connected to the police, fire department, hospitals, army, etc. Deployed as a precaution in case of emergency, these can be used at any time.

Mobile phone
A mobile phone (also known as a cellular phone, cell phone, and a hand phone) is a device that can make and receive telephone calls over a radio link while moving around a wide geographic area. It does so by connecting to a cellular network provided by a mobile phone operator, allowing access to the public telephone network. By contrast, a cordless telephone is used only within the short range of a single, private base station. In addition to telephony, modern mobile phones also support a wide variety of other services such as text messaging, MMS, email, Internet access, short-range wireless communications (infrared, Bluetooth), business applications, gaming and photography. Mobile phones that offer these and more general computing capabilities are referred to as smartphones. The first hand-held mobile phone was demonstrated by John F. Mitchell and Dr Martin Cooper of Motorola in 1973, using a handset weighing around 2.2 pounds (1 kg). In 1983, the DynaTAC 8000x was the first to be commercially available. From 1990 to 2011, worldwide mobile phone subscriptions grew from 12.4 million to over 6 billion, penetrating about 87% of the global population and reaching the bottom of the economic pyramid. Before the devices that are now referred to as mobile phones existed, there were some precursors. The development of mobile telephony began in 1918 with tests of wireless telephony on military trains between Berlin - Zossen. In 1924 public trials started with telephone connection on trains between Berlin - Hamburg. In 1925 is founded to supply train telephony equipment and in 1926 telephone service in trains of the Deutsche Reichsbahn and imperial post on the route between Hamburg and Berlin is approved and used. This phone service was only offered to 1st class travelers, but in 1918, some after the invention of Meißnerischen tube based transmitters, the German Reichsbahn in Berlin led experiments with telephony via radio. The first mobile telephone calls were made from automobiles in 1946. The Bell System's - Mobile Telephone Service - inaugural call was made on 17 June of that year in St. Louis, Missouri, followed by Illinois Bell Telephone Company's car radiotelephone service in Chicago on 2 October. The MTS phones were composed of vacuum tubes and relays, and weighed over 80 pounds (36 kg). There were initially only 3 channels for all the users in the metropolitan area, increasing later to 32 channels across 3 bands. This service continued into the 1980s in large portions of North America. Due to the small number of radio frequencies available, the service quickly reached capacity. In 1956, the world’s first partly automatic car phone system, Mobile System A (MTA), was introduced in Sweden. John F. Mitchell, Motorola's chief of portable communication products in 1973, played a key role in advancing the development of handheld mobile telephone equipment. Mitchell successfully pushed Motorola to develop wireless communication products that would be small enough to use anywhere and participated in the design of the cellular phone. Martin Cooper, a Motorola researcher and executive, was the key researcher on Mitchell's team that developed the first hand-held mobile telephone for use on a cellular network. Using a somewhat heavy portable handset, Cooper made the first call on a handheld mobile phone on 3 April 1973 to his rival, Dr. Joel S. Engel of Bell Labs. The new invention sold for $3,995 and weighed two pounds, leading to the nickname "the brick". The world's first commercial automated cellular network was launched in Japan by NTT in 1979, initially in the metropolitan area of Tokyo. In 1981, this was followed by the simultaneous launch of the Nordic Mobile Telephone (NMT) system in Denmark, Finland, Norway and Sweden. Several countries then followed in the early to mid-1980s including the UK, Mexico and Canada. On 6 March 1983, the DynaTAc mobile phone launched on the first US 1G network by Ameritech. It cost $100m to develop, and took over a decade to reach the market. The phone had a talk time of just half an hour and took ten hours to charge. Consumer demand was strong despite the battery life, weight, and low talk time, and waiting lists were in the thousands. In 1991, the second generation (2G) cellular technology was launched in Finland by Radiolinja on the GSM standard, which sparked competition in the sector as the new operators challenged the incumbent 1G network operators. Ten years later, in 2001, the third generation (3G) was launched in Japan by NTT DoCoMo on the WCDMA standard. This was followed by 3.5G, 3G+ or turbo 3G enhancements based on the high-speed packet access (HSPA) family, allowing UMTS networks to have higher data transfer speeds and capacity. By 2009, it had become clear that, at some point, 3G networks would be overwhelmed by the growth of bandwidth-intensive applications like streaming media. Consequently, the industry began looking to data-optimized 4th-generation technologies, with the promise of speed improvements up to 10-fold over existing 3G technologies. The first two commercially available technologies billed as 4G were the WiMAX standard (offered in the U.S. by Sprint) and the LTE standard, first offered in Scandinavia by TeliaSonera. All mobile phones have a number of features in common, but manufacturers also try to differentiate their own products by implementing additional functions to make them more attractive to consumers. This has led to great innovation in mobile phone development over the past 20 years. The common components found on all phones are: Low-end mobile phones are often referred to as feature phones, and offer basic telephony. Handsets with more advanced computing ability through the use of native software applications became known as smartphones. Several phone series have been introduced to address a given market segment, such as the RIM BlackBerry focusing on enterprise/corporate customer email needs; the Sony-Ericsson 'Walkman' series of music/phones and 'Cybershot' series of camera/phones; the Nokia Nseries of multimedia phones, the Palm Pre the HTC Dream and the Apple iPhone. The most commonly used data application on mobile phones is SMS text messaging. The first SMS text message was sent from a computer to a mobile phone in 1992 in the UK, while the first person-to-person SMS from phone to phone was sent in Finland in 1993. The first mobile news service, delivered via SMS, was launched in Finland in 2000, and subsequently many organizations provided "on-demand" and "instant" news services by SMS. GSM feature phones require a small microchip called a Subscriber Identity Module or SIM Card, to function. The SIM card is approximately the size of a small postage stamp and is usually placed underneath the battery in the rear of the unit. The SIM securely stores the service-subscriber key (IMSI) and the iK used to identify and authenticate the user of the mobile phone. The SIM card allows users to change phones by simply removing the SIM card from one mobile phone and inserting it into another mobile phone or broadband telephony device. The first SIM card was made in 1991 by Munich smart card maker Giesecke & Devrient for the Finnish wireless network operator Radiolinja.][ A hybrid mobile phone can hold up to four SIM cards. SIM and RUIM cards may be mixed together to allow both GSM and CDMA networks to be accessed. From 2010 onwards they became popular in India and Indonesia and other emerging markets, attributed to the desire to obtain the lowest on-net calling rate. In Q3 2011, Nokia shipped 18 million of its low cost dual SIM phone range in an attempt to make up lost ground in the higher end smartphone market. There are Jewish orthodox religious restrictions which standard mobile telephones do not meet. To fulfill this demand, phones without Internet access, text messaging or cameras are required. These restricted phones are known as kosher phones and have rabbinical approval for use in Israel and elsewhere by observant Orthodox Jews. Some are even approved for use by essential workers (such as health, security and public services) on the sabbath, even though use of any electrical device is restricted. Although these phones are intended to prevent immodesty, some vendors report good sales to adults who prefer the simplicity of the devices. The world's largest individual mobile operator by subscribers is China Mobile with over 500 million mobile phone subscribers. Over 50 mobile operators have over 10 million subscribers each, and over 150 mobile operators had at least one million subscribers by the end of 2009. In February 2010, there were 6 billion mobile phone subscribers, a number that is expected to grow. Prior to 2010, Nokia was the market leader. However, since then competition emerged in the Asia Pacific region with brands such as Micromax, Nexian, and i-Mobile and chipped away at Nokia's market share. Android powered smartphones also gained momentum across the region at the expense of Nokia. In India, their market share also dropped significantly to around 31 percent from 56 percent in the same period. Their share was displaced by Chinese and Indian vendors of low-end mobile phones. In Q1 2012, based on Strategy Analytics, Samsung surpassed Nokia, selling 93.5 million units and 82.7 million units, respectively. Standard & Poor's has also downgraded Nokia to 'junk' status at BB+/B with negative outlook due to high loss and still declined with growth of Lumia smartphones was not sufficient to offset a rapid decline in revenue from Symbian-based smartphones over the next few quarters. Other manufacturers outside the top five include TCL Communication, Lenovo, Sony Mobile Communications, Motorola. Smaller current and past players include Karbonn Mobile, Audiovox (now UTStarcom), BenQ-Siemens, BlackBerry, Casio, CECT, Coolpad, Fujitsu, HTC, Just5, Kyocera, Lumigon, Micromax Mobile, Mitsubishi Electric, Modu, NEC, Neonode, Openmoko, Panasonic, Palm, Pantech Wireless Inc., Philips, Qualcomm Inc., Sagem, Sanyo, Sharp, Sierra Wireless, SK Teletech, Soutec, Trium, Toshiba, and Vidalco. Mobile phones are used for a variety of purposes, including keeping in touch with family members, conducting business, and having access to a telephone in the event of an emergency. Some people carry more than one cell phone for different purposes, such as for business and personal use. Multiple SIM cards may also be used to take advantage of the benefits of different calling plans—a particular plan might provide cheaper local calls, long-distance calls, international calls, or roaming. The mobile phone has also been used in a variety of diverse contexts in society, for example: In 1998, one of the first examples of distributing and selling media content through the mobile phone was the sale of ringtones by Radiolinja in Finland. Soon afterwards, other media content appeared such as news, video games, jokes, horoscopes, TV content and advertising. Most early content for mobile tended to be copies of legacy media, such as the banner advertisement or the TV news highlight video clip. Recently, unique content for mobile has been emerging, from the ringing tones and ringback tones in music to "mobisodes," video content that has been produced exclusively for mobile phones. In 2006, the total value of mobile-phone-paid media content exceeded Internet-paid media content and was worth 31 billion dollars. The value of music on phones was worth 9.3 billion dollars in 2007 and gaming was worth over 5 billion dollars in 2007. Mobile phone use while driving is common but controversial. Being distracted while operating a motor vehicle has been shown to increase the risk of accident. Because of this, many jurisdictions prohibit the use of mobile phones while driving. Egypt, Israel, Japan, Portugal and Singapore ban both handheld and hands-free use of a mobile phone; others —including the UK, France, and many U.S. states—ban handheld phone use only, allowing hands-free use. Due to the increasing complexity of mobile phones, they are often more like mobile computers in their available uses. This has introduced additional difficulties for law enforcement officials in distinguishing one usage from another as drivers use their devices. This is more apparent in those countries which ban both handheld and hands-free usage, rather than those who have banned handheld use only, as officials cannot easily tell which function of the mobile phone is being used simply by looking at the driver. This can lead to drivers being stopped for using their device illegally on a phone call when, in fact, they were using the device for a legal purpose such as the phone's incorporated controls for car stereo or satnav. A recently published study has reviewed the incidence of mobile phone use while cycling and its effects on behaviour and safety. Some schools limit or restrict the use of mobile phones. Schools have set restrictions because of the use of cell phones for cheating on tests, harassment and bullying, threats to the school's security, distraction of students, and the facilitating of gossip and other social activity at school. Many mobile phones are banned in school locker room facilities, public restrooms and swimming pools due to the built-in cameras that most phones now feature.][ In many countries, mobile phones are used to provide mobile banking services, which may include the ability to transfer cash payments by secure SMS text message. Kenya's M-PESA mobile banking service, for example, allows customers of the mobile phone operator Safaricom to hold cash balances which are recorded on their SIM cards. Cash may be deposited or withdrawn from M-PESA accounts at Safaricom retail outlets located throughout the country, and may be transferred electronically from person to person as well as used to pay bills to companies. Branchless banking has also been successful in South Africa and Philippines. A pilot project in Bali was launched in 2011 by the International Finance Corporation and an Indonesian bank Bank Mandiri. Another application of mobile banking technology is Zidisha, a US-based nonprofit microlending platform that allows residents of developing countries to raise small business loans from web users worldwide. Zidisha uses mobile banking for loan disbursements and repayments, transferring funds from lenders in the United States to the borrowers in rural Africa using the internet and mobile phones. Mobile payments were first trialled in Finland in 1998 when two Coca-Cola vending machines in Espoo were enabled to work with SMS payments. Eventually, the idea spread and in 1999 the Philippines launched the first commercial mobile payments systems, on the mobile operators Globe and Smart. Some mobile phone can make mobile payments via direct mobile billing schemes or through contactless payments if the phone and point of sale support near field communication (NFC). This requires the co-operation of manufacturers, network operators and retail merchants to enable contactless payments through NFC-equipped mobile phones. Mobile phones are also commonly used to collect location data. While the phone is turned on, the geographical location of a mobile phone can be determined easily (whether it is being used or not), using a technique known as multilateration to calculate the differences in time for a signal to travel from the cell phone to each of several cell towers near the owner of the phone. The movements of a mobile phone user can be tracked by their service provider and, if desired, by law enforcement agencies and their government. Both the SIM card and the handset can be tracked. China has proposed using this technology to track commuting patterns of Beijing city residents. In the UK and US, law enforcement and intelligence services use mobiles to perform surveillance. They possess technology to activate the microphones in cell phones remotely in order to listen to conversations that take place near the phone. According to the Federal Communications Commission, one out of three robberies involved the theft of a cellular phone. Police data in San Francisco showed that one-half of all robberies in 2012 were thefts of cellular phones. An online petition on Change.org called Secure our Smartphones urged smartphone manuacturers to install kill switches in their devices to make them unusable in case of theft. The petition is part of a joint effort by New York Attorney General Eric Schneiderman and San Francisco District Attorney George Gascon and was directed to the CEOs of the major smartphone manufacturers and telecommunication carriers. On Monday, June 10, 2013, Apple announced it would install a kill switch on its next iPhone operating system, due to debut in October 2013. The effect mobile phone radiation has on human health is the subject of recent interest and study, as a result of the enormous increase in mobile phone usage throughout the world. Mobile phones use electromagnetic radiation in the microwave range, which some believe may be harmful to human health. A large body of research exists, both epidemiological and experimental, in non-human animals and in humans, of which the majority shows no definite causative relationship between exposure to mobile phones and harmful biological effects in humans. This is often paraphrased simply as the balance of evidence showing no harm to humans from mobile phones, although a significant number of individual studies do suggest such a relationship, or are inconclusive. Other digital wireless systems, such as data communication networks, produce similar radiation. On 31 May 2011, the World Health Organization stated that mobile phone use may possibly represent a long-term health risk, classifying mobile phone radiation as "possibly carcinogenic to humans" after a team of scientists reviewed studies on cell phone safety. Mobile phones are in category 2B, which ranks it alongside Coffee and other possibly carcinogenic substances. At least some recent studies have found an association between cell phone use and certain kinds of brain and salivary gland tumors. Lennart Hardell and other authors of a 2009 meta-analysis of 11 studies from peer-reviewed journals concluded that cell phone usage for at least ten years “approximately doubles the risk of being diagnosed with a brain tumor on the same ('ipsilateral') side of the head as that preferred for cell phone use.” One study of past cell phone use cited in the report showed a "40% increased risk for gliomas (brain cancer) in the highest category of heavy users (reported average: 30 minutes per day over a 10‐year period)." This is a reversal from their prior position that cancer was unlikely to be caused by cellular phones or their base stations and that reviews had found no convincing evidence for other health effects. Certain countries, including France, have warned against the use of cell phones especially by minors due to health risk uncertainties. However, a study published 24 March 2012 in the British Medical Journal questioned these estimates, because the increase in brain cancers has not paralleled the increase in mobile phone use. 5G is a technology used in research papers and projects to denote the next major phase of mobile telecommunication standards beyond the 4G/IMT-Advanced standards. 5G is not officially used for any specification or official document yet made public by telecommunication companies or standardization bodies such as 3GPP, WiMAX Forum, or ITU-R. New standard releases beyond 4G are in progress by standardization bodies, but are at this time not considered as new mobile generations but under the 4G umbrella. Deloitte is predicting a collapse in wireless performance to come as soon as 2016, as more devices using more and more services compete for limited bandwidth. Studies have shown that around 40-50% of the environmental impact of a mobile phone occurs during the manufacturing of the printed wiring boards and integrated circuits. The average user replaces their mobile phone every 11 to 18 months. The discarded phones then contribute to electronic waste. Mobile phone manufacturers within Europe are subject to the WEEE directive. Australia introduced a mobile phone recycling scheme. FairPhone is an attempt to develop a mobile phone which does not contain conflict minerals. CDMA2000 1xEV-DO Revision A (TIA/EIA/IS-856-A)

Telephone number
A telephone number or phone number is a sequence of digits used to call from one telephone line to another in a public switched telephone network. When telephone numbers were invented, they were short — as few as one, two or three digits — and were given orally to a switchboard operator. As phone systems have grown and interconnected to encompass the world, telephone numbers have become longer. In addition to telephones, they now access other devices, such as computers and fax machines. The number contains the information necessary to identify uniquely the intended endpoint for the telephone call. Each such endpoint must have a unique number within the public switched telephone network. Most countries use fixed length numbers (for normal lines at least) and therefore the number of endpoints determines the necessary length of the telephone number. It is also possible for each subscriber to have a set of shorter numbers for the endpoints most often used. These "shorthand" or "speed calling" numbers are automatically translated to unique telephone numbers before the call can be connected. Some special services have their own short numbers (e.g., 1-1-9, 9-1-1, 0-0-0, 9-9-9, 1-1-1, and 1-1-2 being the Emergency Services numbers for China, Japan, South Korea, Taiwan and Sri Lanka; Canada and the United States; Australia; the United Kingdom, Ireland, South Africa, Poland, Saudi Arabia, the United Arab Emirates, Morocco, Macao, Bahrain, Qatar, Bangladesh, Botswana, Ghana, Kenya, Hong Kong, Malaysia, Mauritius, Singapore, Zimbabwe, Trinidad, Tobago; New Zealand; Kuwait and the European Union, respectively.) Many systems also allow calls within a local area to be made without dialing the local area code. For example, a phone number in North America will start with three numbers (such as 661), which is the area code, followed by seven digits split into sections of three and four (such as 550-1212), which is the local number. Some areas now have mandatory ten-digit dialing in place, even for local calls. Most telephone networks today (exceptions being private intercom and secure phone networks) are interconnected in the international telephone network, where the format of telephone numbers is standardized by ITU-T in the recommendation E.164. This specifies that the entire number should be 15 digits or shorter, and begin with a country prefix. For most countries, this is followed by an area code or city code and the subscriber number, which might consist of the code for a particular telephone exchange. ITU-T recommendation E.123 describes how to represent an international telephone number in writing or print, starting with a plus sign ("+") and the country code. When calling an international number from a fixed line phone, the + must be replaced with the international call prefix chosen by the country the call is being made from. Some mobile phones allow the + to be entered directly. The format and allocation of local phone numbers are controlled by each nation's respective government, either directly or by sponsored organizations (such as NANPA overseen by NeuStar Inc.). Before a telephone call is connected, the telephone number must be dialed by the calling party or Caller. The called party might have equipment that presents caller ID before the call is answered. In the late 1870s the Bell interests started utilizing their patent with a rental scheme, in which they would rent their instruments to individual users who would contract with other suppliers to connect them, for example from home to office to factory. Western Union and the Bell company both soon realized that a subscription service would be more profitable, with the invention of the telephone switchboard or central office. Such an office was staffed by an operator who connected the calls by personal names. The latter part of 1879 and the early part of 1880 saw the first use of telephone numbers at Lowell, Massachusetts. During an epidemic of measles, the physician, Dr. Moses Greeley Parker, feared that Lowell's four telephone operators might all succumb to sickness and bring about a paralysis of telephone service. He recommended the use of numbers for calling Lowell's more than 200 subscribers so that substitute operators might be more easily trained in the event of such an emergency. Parker was convinced of the telephone's potential, began buying stock, and by 1883 he was one of the largest individual stockholders in both the American Telephone Company and the New England Telephone and Telegraph Company. Even after the assignment of numbers, operators still connected most calls into the early 20th century; "Hello Central, get me Underwood-342." Connecting through operators or "Central" was the norm until mechanical direct-dialing of numbers became more common in the 1920s. In rural areas with magneto crank telephones connected to party lines, the local phone number consisted of the line number plus the ringing pattern of the subscriber. To dial a number such as "3R122" meant making a request to the operator the third party line (if making a call off your own local one), followed by turning the telephone's crank once, a short pause, then twice and twice again.][ Also common was a code of long and short rings, so one party's call might be signaled by two longs and another's by two longs followed by a short. It was not uncommon to have over a dozen ring cadences (and subscribers) on one line. In North America, the digits 2–9 of phone numbers were allotted 3 letters of the alphabet apiece. This left room for only 24 letters, so the uncommon letters Q and Z were omitted. Phone numbers were not so usually strictly numeric until the mid-1960s. From the 1920s until then, most urban areas had "exchanges" of two letters, followed by numbers, e.g., EDgewood, IVanhoe. In the UK, exchanges in the major cities with Director installations were represented by three letters followed by four numbers; the letters usually represented the name of the exchange area, e.g., MAYfair, WATerloo, or something memorable about the locality (e.g., POPesgrove — an area where Alexander Pope once lived). This was considered easier to remember, although in London in the later part of this period it required the memorization of 7 characters (roughly the same number of characters as is usual for local calling in 2008). A word would represent the first two digits to be dialed, for example "TWinbrook" for "89" ; "BYwater" for "29". UK numbers had no letters at all except for those in the Director areas, where the first three of the seven digits were assigned letters, and written "ABBey 1234" or "WHItehall 1212", for example. A lack of pronounceable words, and the fact that most telephones world-wide have no letters on anyway, have led to the abandonment of letter usage in directory numbers except for publicity purposes. The use of numbers starting in 555- (KLondike-5) to represent fictional numbers in U.S. movies, television, and literature originated in this period. The "555" prefix was reserved for telephone company use and was only consistently used for Directory Assistance (Information), being "555-1212" for the local area. An attempt to dial a 555 number from a movie in the real world will always result in an error message when dialed from a phone in the United States. This reduces the likelihood of nuisance calls. Also, QUincy(5-5555) was used, because there was no Q available. Phone numbers were traditionally tied down to a single location; because exchanges were "hard-wired", the first 3 digits of any number were tied to the geographic location of the exchange. Because the switches were hard-wired together and fairly hard to re-wire (or re-grade), telephone exchange buildings in many larger cities in North America were dedicated to circuits that began with the first two or three digits of the standard 7 digit phone numbers. In a holdover from the days of plug-board exchanges, the exchanges were typically named with a name whose first two letters translated to the digits of the exchange's prefix on a common telephone dial. Examples: CAstle (22), TRinity (87), MUtual (68), and KLondike (55). Certain number combinations were not amenable to this naming process, such as "57," "95" and "97". It was in part due to this factor that telephone exchange names were finally abandoned, since more numbers were needed to prevent a given Area Code from running out of available numbers. In the past, the first two or three digits could be represented by a mnemonic exchange name, e.g., 869-1234 was formerly TOwnsend 9-1234, and before that (in some localities) might have been TOWnsend 1234 (only the capital letters and numbers being dialed) or it could have been TOwnsend 1234 (86-1234) In December 1930, New York City became the first city in the United States to adopt the two-letter, five-number format. It remained alone in this respect until well after World War II, when other municipalities across the country began to follow suit. From the 1920s through the 1950s, most larger American cities used the Bell System standard format of two letters which began the exchange name followed by four numbers, as in DUnkirk 0799. Prior to the mid-1950s, the number immediately following the name could never be a "0" or "1" - indeed, "0" was never pressed into service at all, except in the immediate Los Angeles area. (The "Bensonhurst 0" exchange mentioned in an episode of the former TV sitcom The Honeymooners was a fictitious one.)][ In 1955, the Bell System attempted to standardize the process of naming exchanges by issuing a "recommended list" of names to be used for the various number combinations. In 1961, the New York Telephone Company introduced "selected-letter" exchanges, in which the two letters did not mark the start of any particular name (example: LT 1-7777, once the number of the main switchboard at ABC][ ), and by 1965 all newly-connected phone numbers nationwide consisted of numerals only. (Wichita Falls, Texas, had been the first locality in the United States to implement the latter, having done so in 1958.) Pre-existing numbers continued to be displayed the old way in many places well into the 1970s. For example Boushelle, a company outside Chicago, still uses HUdson3-2700 in their commercials. Because the pulses from a rotary dial (as used to operate switches in a Strowger exchange) took time, having a phone number with lots of 8s, 9s, or 0s meant it took longer to dial the number. The phone companies typically assigned such "high" numbers to pay phones because they were rarely dialed to. Fictitious telephone numbers are often used in films and on television to avoid real numbers being called by viewers. The "555" (or Klondike-5) exchange was never assigned any real numbers (with limited exceptions such as 555-1212 for directory assistance), which is why today's TV and movie shows use 555-xxxx numbers for their phone numbers (previously, such productions often used numbers that ended in certain four-number combinations that were typically set aside for similar uses — "0079" on the West Coast and "9970" in many other places; examples include the TV series Perry Mason and the 1948 film Sorry, Wrong Number). "Klondike-5" was also heard in the Perry Mason show and in Seinfeld. That way there was no possibility that a fake number from a show would actually reach someone, thus avoiding the scenario which arose in 1982 with Tommy Tutone's hit song "867-5309/Jenny". This song led to many customers who actually had that number receiving a plethora of unwanted calls. In fact, many American phone companies either no longer assign this number, or they have relegated it to internal testing purposes.][ As of early August 2009, (267) 867-5309, which is assigned to the suburban Philadelphia area, was being auctioned on eBay. Bidding is in excess of $5,000 USD. However, today only numbers beginning with 555-01xx are reserved for fiction and other 555-numbers can be allocated to "information providers". A side effect of the fictional-number pool being reduced to 100 numbers is that the same ones now often recur in different movies or TV shows. The "958" and "959" prefixes are reserved for telephone engineering test purposes in most localities, and as a result very few individuals or businesses have telephone numbers beginning with those sets of digits either (although this fact is not as well known, so no such numbers have been used in a fictional context). The number in the Glenn Miller Orchestra's hit song "Pennsylvania 6-5000" is the number of the Hotel Pennsylvania in New York City, and was issued in 1919.][ The number is now written as (212) 736-5000. According to the hotel's website, Pennsylvania 6-5000 is New York's oldest continually assigned telephone number, and possibly the oldest continuously-assigned number in the world. In 2003, the movie Bruce Almighty originally featured a number that did not have the 555 prefix. In the movie, God (Morgan Freeman) left the number for Bruce Nolan (Jim Carrey) to call if he needed God's help. According to Universal Studios, which produced the movie, the number it used was picked because it did not exist in Buffalo, New York where the movie was set. However, the number did exist in other cities, resulting in customers having that number receiving random calls from people asking for God. While some played along with the gag, others found the calls aggravating. The number was reportedly changed when the movie was released on DVD. Martin Scorsese's After Hours contains a working phone number in it, 243-3460, but no area code is explicitly given. In the Disney film The Computer Wore Tennis Shoes, a 247 number was given to a pay phone. This was because the writer of the script, Joe McEveety, used his own number in the film. In a scene from another Disney film, Bolt, the number (877) 504-8423 is seen printed on a flyer. The number is reserved by ABC, as evidenced by the brief recorded message heard when the number is called, which reads "Thank you for calling ABC. The number you have reached is a fictional non-working number used for motion picture and television production." The 1995 film Heat contains phone numbers for pay phones that have 1 as the first digit. One such number, for a pay phone read by Danny Trejo's character to Robert De Niro's, is 103-7206. In the UK, letters were assigned to numbers in a similar fashion as in North America, except that the letter O was allocated to the digit 0 (zero); digit 6 had only M and N. The letter Q was later added to the zero position on British dials in anticipation of direct international dialing to Paris which commenced in 1963. This was necessary because French dials already had Q on the zero position, and there were exchange names in the Paris region which contained the letter Q. Most of the United Kingdom had no lettered telephone dials until the introduction of Subscriber Trunk Dialing (STD) in 1958. Prior to that time, only the director areas (Birmingham, Edinburgh, Glasgow, Liverpool, London and Manchester) and the adjacent non-director areas had the lettered dials; the director exchanges used the three-letter, four-number format. With the introduction of trunk dialing, the need for all callers to be able to dial numbers with letters in them led to the much more widespread use of lettered dials. The need for dials with letters was finally abandoned with the conversion to all-digit numbering in 1968. In the middle 20th century in North America when a call could not be completed, for example because the phone number was not assigned, had been disconnected, or was experiencing technical difficulties, it went to an intercept operator who informed the caller. In the 1970s this service was converted to Automatic Intercept Systems which automatically chooses and presents an appropriate intercept message. Disconnected numbers are reassigned to new users after the rate of calls to them declines. Outside of North America, operator intercept was rare, and in most cases calls to unassigned or disconnected numbers would result in a recorded message or number-unobtainable tone being returned to the caller.

Called party
The called party (in some contexts called the "B-Number") is a person who (or device that) answers a telephone call. The person who (or device that) initiates a telephone call is the calling party. In some situations, the called party may number more than one: such an instance is known as a conference call. Strictly, in some systems, only one called party is contacted at each event, as to initiate a conference call the calling party contacts the first called party, then this person contacts the second called party, but audio is transferred to both called parties. In a collect call (i.e. reverse charge), the called party pays the fee for the call, when it is usually the calling party that does so. The called party also pays if the number dialed is a toll-free telephone number. In some countries, such as the United States and China, users of mobile phones pay for the "airtime" to receive calls, while in other countries, e.g. most European countries, the elevated interconnect fees are paid fully by the calling party and the called party are kept free of charge. 3pcc

Windows Mobile
Windows Mobile is a family of mobile operating systems developed by Microsoft for smartphones and Pocket PCs. Windows Mobile is the predecessor of Windows Phone. In February 2010, Microsoft announced Windows Phone to supersede Windows Mobile. As a result, Windows Mobile has been deprecated. Windows Phone is incompatible with Windows Mobile devices and software. The last version of Windows Mobile, released after the announcement of Windows Phone, was 6.5.5. Most versions of Windows Mobile have a set of standard features, such as multitasking and the ability to navigate a file system similar to that of Windows 9x and Windows NT, with support for many of the same file types. Much like its desktop counterpart, it comes bundled with a set of applications to perform basic tasks. Internet Explorer Mobile is the default web browser and Windows Media Player is the default media player used for playing digital media. Microsoft Office Mobile, the mobile versions of Microsoft Office, is the default office suite. Internet Connection Sharing, supported on compatible devices, allows the phone to share its Internet connection with computers via USB and Bluetooth. Windows Mobile support virtual private networking (VPN) over PPTP protocol. Most devices with mobile connectivity include a Radio Interface Layer (RIL). RIL provides the system interface between the CellCore layer within the Windows Mobile OS and the radio protocol stack used by the wireless modem hardware. This allows OEMs to integrate a variety of modems into their equipment. The user interface has changed much between versions but the basic functionality has remained similar. Today Screen, later called the Home Screen, shows the current date, owner information, upcoming appointments, e-mail messages, and tasks. Taskbar shows the current time and the audio volume and of devices with a cellular radio the signal strength. Windows Mobile has supported third party software the original Pocket PC implementations. Windows Mobile was based on the Windows CE kernel and first appeared as the Pocket PC 2000 operating system. It was supplied with a suite of basic applications developed with the Microsoft Windows API, and is designed to have features and appearance somewhat similar to desktop versions of Windows. Third parties can develop software for Windows Mobile with no restrictions imposed by Microsoft. Software applications were purchasable from Windows Marketplace for Mobile during the service's lifespan. Most early Windows Mobile devices came with a stylus, which can be used to enter commands by tapping it on the screen. The primary touch input technology behind most devices were resistive touchscreens which often required a stylus for input. Later devices used capacitive sensing which does not require a stylus. Along with touchscreens a large variety of form factors existed for the platform. Some devices featured slideout keyboards, while others featured minimal face buttons. Microsoft's work on handheld portable devices began with research projects in 1990, two years later work on Windows CE officially began. Initially the OS and the user interface were developed separately. With Windows CE being based on Windows 95 code and a separate team handing the user interface which was codenamed WinPad(later Microsoft At Work for Handhelds). Windows 95 had strong pen support making porting easy; with some saying "At this time, Windows 95 offers outstanding pen support. It is treating pens right for the first time." WinPad was delayed due to price and performance issues, before being scrapped in early 1995 due to touchscreen driver problems relating to WriteTouch technology, made by NCR Microelectronic Products. Although WinPad was never released as a consumer product, Alpha builds were released showcasing many interface elements. During development of WinPad a separate team worked on a project called Pulsar; designed to be a mobile communications version of WinPad, described as a "pager on Steroids". This project was also canceled around the same time as WinPad. The two disbanded groups would form the Pegasus project in 1995. Pegasus would work on the hardware side of the Windows CE OS, attempting to create a form factor similar to a PC-esque PDA like WinPad, with communications functionality like Pulsar. A hardware reference guide was created and devices began shipping in 1996, although most of these device bore little resemblance to the goal of a pen-based touchscreen handheld device. Pocket PC 2000, originally codenamed "Rapier", was released on April 19, 2000, and was based on Windows CE 3.0. It was the debut of what was later dubbed the Windows Mobile operating system, and meant to be a successor to the operating system aboard Palm-Size PCs. Backwards compatibility was retained with such Palm-Size PC applications. Pocket PC 2000 was intended mainly for Pocket PC devices, however several Palm-Size PC devices had the ability to be updated also. Further, several Pocket PC 2000 phones were released, however Microsoft's "Smartphone" hardware platform was not yet created. The only resolution supported by this release was 240 x 320 (QVGA). Removable storage card formats that were supported were CompactFlash and MultiMediaCard. At this time Pocket PC devices had not been standardized with a specific CPU architecture. As a result, Pocket PC 2000 was released on multiple CPU architectures; SH-3, MIPS, and ARM. Infrared (IR) File beaming capability was among the original hardware features. The original Pocket PC operating system had similar appearance to Windows 98, Windows Me, and Windows 2000 operating systems. This initial release had multiple built-in applications, many of them similarly branded to match their desktop counterparts; such as Microsoft Reader, Microsoft Money, Pocket Internet Explorer and Windows Media Player. A version of Microsoft's Office suite called Pocket Office was also bundled and included Pocket Word, Pocket Excel and Pocket Outlook. Notes, a written and sound note-taking application saw its first release and would be supported by most later versions of Windows Mobile. Character recognition support allowed Notes to distinguish styles of handwriting to be learned by the OS during processing to improve accuracy and recognition levels. Pocket PC 2002, originally codenamed "Merlin", was released in October 2001. Like Pocket PC 2000, it was powered by Windows CE 3.0. Although targeted mainly for 240 × 320 (QVGA) Pocket PC devices, Pocket PC 2002 was also used for Pocket PC phones, and for the first time, Smartphones. These Pocket PC 2002 Smartphones were mainly GSM devices. With future releases, the Pocket PC and Smartphone lines would increasingly collide as the licensing terms were relaxed allowing OEMs to take advantage of more innovative, individual design ideas. Aesthetically, Pocket PC 2002 was meant to be similar in design to the then newly released Windows XP. Newly added or updated programs include Windows Media Player 8 with streaming capability; MSN Messenger, and Microsoft Reader 2, with Digital rights management support. Upgrades to the bundled version of Office Mobile include a spell checker and word count tool in Pocket Word and improved Pocket Outlook. Connectivity was improved with file beaming on non-Microsoft devices such as Palm OS, the inclusion of Terminal Services and Virtual Private Networking support, and the ability to synchronize folders. Other upgrades include an enhanced UI with theme support and savable downloads and WAP in Pocket Internet Explorer. Windows Mobile 2003, originally codenamed "Ozone", was released on June 23, 2003, and was the first release under the Windows Mobile banner. It came in four editions: "Windows Mobile 2003 for Pocket PC Premium Edition", "Windows Mobile 2003 for Pocket PC Professional Edition", "Windows Mobile 2003 for Smartphone" and "Windows Mobile 2003 for Pocket PC Phone Edition". The last was designed especially for Pocket PCs which include phone functionalities. The Professional Edition was used in Pocket PC budget models. It lacked a number of features that were in the Premium Edition, such as a client for L2TP/IPsec VPNs. Windows Mobile 2003 was powered by Windows CE 4.20. Communications interface were enhanced with Bluetooth device management. Which allowed for Bluetooth file beaming support, Bluetooth headset support and support for Bluetooth add-on keyboards. A pictures application with viewing, cropping, e-mail, and beaming support was added. Multimedia improvements included MIDI file support as ringtones in Phone Edition and Windows Media Player 9.0 with streaming optimization. A puzzle game titled Jawbreaker is among the preinstalled programs. GAPI was included with this release to facilitate the development of games for the platform. Other features/built-in applications included the following: enhanced Pocket Outlook with vCard and vCal support, improved Pocket Internet Explorer and SMS reply options for Phone Edition. Windows Mobile 2003 Second Edition, also known as "Windows Mobile 2003 SE", was released on March 24, 2004 and first offered on the Dell Axim x30. This was the last version which allowed users to back up and restore an entire device through ActiveSync. This upgrade allows users to switch between Portrait and Landscape modes and introduces a single-Column layout in Pocket Internet Explorer. To make wireless internet access more secure Wi-Fi Protected Access (WPA) support was added. An array of new screen resolutions also debuted;VGA (640×480), 176х220, 240x240, and 480x480, to increase visual clarity and the range of form factors Windows Mobile could run on. Windows Mobile 5.0, originally codenamed "Magneto", was released at Microsoft's Mobile and Embedded Developers Conference 2005 in Las Vegas, May 9–12, 2005. Microsoft offered mainstream support for Windows Mobile 5 through October 12, 2010, and extended support through October 13, 2015. It was first offered on the Dell Axim x51. It used the .NET Compact Framework 1.0 SP3, an environment for programs based on .NET. Windows Mobile 5.0 included Microsoft Exchange Server "push" functionality improvements that worked with Exchange 2003 SP2. The "push" functionality also required vendor/device support With AKU2 software upgrades all WM 5.0 devices supported DirectPush. This version featured increased battery life due to Persistent storage capability. Previously up to 50% (enough for 72 hours of storage) of battery power was reserved just to maintain data in volatile RAM. This continued the trend of Windows-based devices moving from using RAM as their primary storage medium to the use of a combination of RAM and flash memory (in use, no distinction between the two is obvious to users). Programs and frequently accessed data run in RAM, while most storage is in the flash memory. The OS seamlessly moves data between the two as needed. Everything is backed up in the flash memory, so unlike prior devices, WM5 devices lose no data if power is lost. New to 5.0, OS updates were released as Adaptation kit upgrades, with AKU 3.5 being the final released. A new version of Office was bundled called "Microsoft Office Mobile" with includes PowerPoint Mobile, Excel Mobile with graphing capability and Word Mobile with the ability to insert tables and graphics. Media management and playback was enhanced with Picture and Video package, which converged the management of videos and pictures and Windows Media Player 10 Mobile. Among new hardware features were enhanced Bluetooth support, default QWERTY keyboard-support and a management interface for Global Positioning System (GPS). Improvements were made to ActiveSync 4.2 with 15% increased synchronization speed. Business customers benefited from a new error reporting facility similar to that present in desktop and server Windows systems. Caller ID now supports photos so a user can apply an image to each contact to show when a call is received. DirectShow was also natively added. This release was the first to include DirectDraw with hardware acceleration, replacing the deprecated graphics component of GAPI Windows Mobile 5.0 requires at least 64 MBs of ROM (it's advisable to have 64 MBs of RAM), and the device must run an ARM compatible processor such as the Intel XScale or the Samsung and Texas Instruments ARM compatibles. Windows Mobile 6, formerly codenamed "Crossbow", was released on February 12, 2007 at the 3GSM World Congress 2007. It comes in three different versions: "Windows Mobile 6 Standard" for Smartphones (phones without touchscreens), "Windows Mobile 6 Professional" for Pocket PCs with phone functionality, and "Windows Mobile 6 Classic" for Pocket PCs without cellular radios. Windows Mobile 6 is powered by Windows CE 5.0 (version 5.2) and is strongly linked to the then newly introduced Windows Live and Exchange 2007 products. Windows Mobile 6 Standard was first offered on the Orange's SPV E650, while Windows Mobile 6 Professional was first offered on the O2's Xda Terra. Aesthetically, Windows Mobile 6 was meant to be similar in design to the then newly released Windows Vista. Functionally, it works much like Windows Mobile 5, but with much better stability. Along with the announcement of Office Mobile 6.1 with support for Office 2007 document formats (pptx, docx, xlsx); OneNote Mobile, a companion to Microsoft Office OneNote was added to the already installed version. In addition to the newly included programs with Office Mobile improvements were made to existing applications. Such as HTML email support in Outlook Mobile. A large number of Windows Mobile users are enterprise users business environments were targeted. With Server Search on Microsoft Exchange 2007, Out of Office Replies with Microsoft Exchange 2007, and search ability for contacts in an Exchange Server Address Book being implemented. To aid development for programmers, .NET Compact Framework v2 SP2 is now preinstalled with the OS. Developers and users also have access to Microsoft SQL Server 2005 Compact Edition for storage and retrieval of information. AJAX, JavaScript, and XMLDOM support were added to Internet Explorer Mobile along with improved devicewide Internet Sharing. Communication abilities were further enhanced with a new Microsoft Bluetooth Stack and VoIP (Internet calling) support with AEC (Acoustic Echo Cancelling) and MSRT Audio Codec. To improve security Microsoft added Storage Card Encryption so that encryption keys are lost if device is cold-booted. Further updates both, security and feature, can now also be provided using Operating System Live Update Among other improvements: 320x320 and 800x480 (WVGA) screen resolution support (The S01SH or "Em One" by Sharp was the first and only device to have a 800x480 screen on WM5), Improved Remote Desktop access (Available for only certain Pocket PCs), Customer Feedback option, Smartfilter for searching within programs and Unlicensed Mobile Access (UMA) support for select operators Windows Mobile 6.1 was announced April 1, 2008. It is a minor upgrade to the Windows Mobile 6 platform with various performance enhancements and a redesigned Home screen featuring horizontal tiles that expand on clicking to display more information, although this new home screen is featured only on Windows Mobile Standard edition. This was not supported in the Professional edition. Several other changes such as threaded SMS, full page zooming in Internet Explorer and 'Domain Enroll' were also added, along with a "mobile" version of the Microsoft OneNote program and an interactive "Getting Started" wizard. Domain Enroll is functionality to connect the device to System Center Mobile Device Manager 2008, a product to manage mobile devices. The most apparent of the other differences is that the Standard version (like prior versions) still creates automatic links for telephone numbers in Tasks and Appointments, which allows for the easier click and dial of stored telephone numbers within these Outlook items. This feature is not supported in the Professional version. Windows Mobile 6.1 also had improved bandwidth efficiency in its push-email protocol "Activesync" of "up to 40%"; this considerably improved battery life in many devices. Aside from the visual and feature distinctions, the underlying CE versions can be used to differentiate WM6.0 from WM 6.1. The version of Windows CE in WM 6.0 is 5.2.*, with the final number being a 4 digit build ID (e.g. 5.2.1622 on HTC Wing). In WM 6.1, the CE version is 5.2.* with a 5 digit build number (e.g. 5.2.19216 on Palm Treo 800w). Windows Mobile 6.5 was a stopgap update to Windows Mobile 6.1 intended to bridge the gap between version 6.1 and the then yet-to-be released Windows Mobile 7 (Later renamed Windows Phone 7), that arrived in 2010. It was never part of Microsoft's mobile phone roadmap, and has been described by its chief executive, Steve Ballmer, as "not the full release [Microsoft] wanted" until the multi-touch-enabled Windows Mobile 7 (now replaced by Windows Phone) arrived in 2010. Ballmer also indicated that the company "screwed up with Windows Mobile", he lamented that Windows Mobile 7 was not yet available and that the Windows Mobile team needed to try to recoup losses. Microsoft unveiled this version at the 2009 Mobile World Congress in February, and several devices were supplied with it. It was released to manufacturers on May 11, 2009; the first devices running the operating system appeared in late October 2009. Several phones that officially shipped with Windows Mobile 6.1 can be officially updated to Windows Mobile 6.5. This update includes some significant new added features, such as a revamped GUI, a new Today screen resembling that of Microsoft's Zune player with vertically scrollable labels (called 'Titanium'). WM6.5 also includes the new Internet Explorer Mobile 6 browser, with improved interface. Along with Windows Mobile 6.5, Microsoft announced several Cloud computing services codenamed "SkyBox", "SkyLine", "SkyMarket". "SkyBox" has been confirmed as My Phone, while "SkyMarket" has been confirmed as Windows Marketplace for Mobile. This version was designed mainly for easier finger usage. Some reviewers have noted interface inconsistencies, with some applications having small buttons making them harder to operate using only a finger. Whilst this version of Windows Mobile does not natively support capacitive screens, mobile manufacturers have been able to use them on their devices In the months following this release, development shifted from Windows Mobile to its successor Windows Phone. As such no major upgrades were planned or released, although three minor updates; 6.5.1, 6.5.3 and 6.5.5; were made to satisfy consumers during the transition period. 6.5.1 brings larger user interface elements, including icon based soft buttons (rather than text based), an updated contacts app, native support for A-GPS, improved threaded text messaging, and performance improvements. It was unofficially ported to several Windows Mobile phones. The second minor update was announced on February 2, 2010, along with the Sony Ericsson Aspen which was the first phone to use this version. 6.5.3 continues the trend of attempting to provide a more finger-friendly user interface with several new usability features such as native support for multitouch; although device maker HTC Corporation created proprietary work-arounds to allow multi-touch to work on some applications it installed on its HD2 handset(However, Microsoft applications on this handset, such as the Internet Explorer web browser, did not support multi-touch.) and drag-and-drop start menu icons. Touchable tiles replaced soft keys." Internet Explorer Mobile 6 has also received some major updates including decreased page load time, improved memory management and gesture smoothing. As with other updates it was unofficially ported to some other devices. Additional features include threaded email and Office Mobile 2010. The last minor update and the last released version is 6.5.5. It first leaked in January 2010, and was unofficially ported to some Windows Mobile phones. The name Windows Mobile 6.5.5 has been applied to these newer builds, although this name remained unconfirmed by Microsoft. There are three main versions of Windows Mobile for various hardware devices: Windows Mobile for Automotive and Windows Mobile software for Portable Media Centers are among some specialty versions of the platform. Microsoft had over 50 handset partners, when Windows Mobile was still being shipped on new devices. 80% of the 50 million Windows Mobile devices that were made from launch to February 2009 were built by one contract manufacturing group, HTC, which makes handsets for several major companies under their brands, and under its own brand. On January 10, 2011, Microsoft announced Windows Embedded Handheld 6.5. The operating system has compatibility with Windows Mobile 6.5 and is presented as an enterprise handheld device, targeting retailers, delivery companies, and other companies that rely on handheld computing. Unlike Windows Phone, Windows Embedded Handheld retains backward compatibility with legacy Windows Mobile applications. Pocket PCs and personal digital assistants were originally the intended platform for Windows Mobile. These were grouped into two main categories: devices that lacked mobile phone capabilities, and those that included it. Beginning with version 6 devices with this functionality ran "Windows Mobile 6 Professional" and those that lacked it ran "Windows Mobile 6 Classic". Microsoft had described these devices as "a handheld device that enables you to store and retrieve e-mail, contacts, appointments, play multimedia files, games, exchange text messages with MSN Messenger, browse the Web, and more". From a technical standpoint Microsoft also specified various hardware and software requirements such as the inclusion of a touchscreen and a directional pad or touchpad. Smartphones were the second hardware platform after Pocket PC to run Windows Mobile, and debuted with the release of Pocket PC 2002. Although in the broad sense of the term "Smartphone", both Pocket PC phones and Microsoft branded Smartphones each fit into this category, it should be noted that Microsoft's use of the term "Smartphone" includes only more specific hardware devices that differ from Pocket PC phones. Such Smartphones were originally designed without touchscreens, intended to be operated more efficiently with only one hand, and typically had lower display resolution than Pocket PCs. Microsoft's focus for the Smartphone platform was to create a device that functioned well as a phone and data device in a more integrated manner. Windows Mobile's share of the smartphone market grew from its inception while new devices were being released. Peaking in 2007, after which it saw decline year-on-year. In Q1 2004, Windows Mobile accounted for 23% of worldwide smartphone sales. Windows Mobile was projected to overtake Symbian to become the leading mobile OS by 2010. In Q4 2005 Microsoft shipped 2.2 million PDAs, which increased to 3.5 million in the same quarter the following year. Windows Mobile saw year over year growth between 2005–2006 of 38.8% which according to Gartner "helped Windows Mobile to solidify its stronghold on the market". But by 2008, its share had dropped to 14%. Microsoft licensed Windows Mobile to four out of the world's five largest mobile phone manufacturers, with Nokia being the exception. Gartner research data showed that while the total smartphone industry grew 27% between 2008 and 2009, Windows Mobile's share of the smartphone market fell 2.7% in that same period. It also decreased by 20% in Q3 2009. At one time Windows Mobile was the most popular handset for business use,][ but by 2009 this was no longer the case; 24% of planned business deployments of mobile application were for Windows Mobile, putting it in 3rd place, behind Blackberry (61%) and iPhone (27%); In February 2009 Microsoft signed a deal with the third largest mobile phone maker, LG Electronics, to license Windows Mobile OS on 50 upcoming LG smartphone models. But in September 2009, Palm, Inc. announced it would drop Windows Mobile from its smartphone line-up. Gartner estimated that by the third quarter of 2009 Windows Mobile's share of worldwide smartphone sales was 7.9%. By August 2010, it was the least popular smartphone operating system, with a 5% share of the worldwide smartphone market (after Symbian, BlackBerry OS, Android and iOS). An October 2009 report in DigiTimes said that Acer will shift its focus from Windows Mobile to Google Android. The New York Times reported in 2009 that Windows Mobile "is foundering", as cellphone makers desert it in favor of Google's Android phone platform. It cited the difficulties in Microsoft's business model, which involves charging handset manufacturers up to $25 for each copy of Windows Mobile, while rival Google gives away Android for free. From late 2009 analysts and media reports began to express concerns about the future viability of the Windows Mobile platform, and whether Microsoft would keep supporting it into the future. Samsung announced in November 2009 that it would phase out the Windows Mobile platform, to concentrate on its own Bada operating system, Google's Android, and Microsoft's Windows Phone. Software may be developed by third parties for the Windows Mobile operating system. Developers have several options for deploying mobile applications. These include writing native code with Visual C++, managed code that works with the .NET Compact Framework, writing code in Tcl-Tk with eTcl, GCC using CeGCC, Python using PythonCE or server-side code that can be deployed using Internet Explorer Mobile or a mobile client on a user's device. The .NET Compact Framework is a subset of the .NET Framework and hence shares many components with software development on desktop clients, application servers, and web servers which have the .NET Framework installed, thus integrating networked computing space. To aid developers Microsoft released software development kits (SDKs) that work in conjunction with their Visual Studio development environment. These SDKs include emulator images for developers to test and debug their applications while writing them. Software can be tested on a client machine directly or be downloaded to a device. Microsoft also distributes Visual Studio 2008 / 2005 Professional Editions, and server / database counterparts to students as downloads free of charge via its DreamSpark program. Third party integrated development environments can also be used to write software such as Lazarus, Resco MobileForms Toolkit, Lexico, NS Basic and Basic4ppc. Some third party development environments allow coding to be done on the device itself without the need for a computer. Developer communities have used the SDK to port later versions of Windows Mobile OS to older devices and making the OS images available for free, thus providing the devices with the current feature set. Microsoft has tolerated this procedure for some time but decided in February 2007 to ask developers to take their OS images off the net, which in turn raised discussions. At the same time Microsoft offered upgrades to Windows Mobile 6 versions to manufacturers for free. Windows Mobile applications are strongly encouraged to be optimized for touch screen user interfaces. The developer also needs to take into the account the lower CPU performance of older devices. On July 5, 2009, Microsoft opened a third-party application distribution service called Windows Marketplace for Mobile. In 2011, Windows Marketplace for Mobile stopped accepting new admissions. and then fully closed on May 9, 2012. In the early years of Windows Mobile devices were able to be managed and synced from a remote computer using ActiveSync; a data synchronization technology and protocol developed by Microsoft, originally released in 1996. This allowed servers running Microsoft Exchange Server, or other third party variants, to act as a personal information manager and share information such as email, calendar appointments, contacts or internet favorites. With the release of Windows Vista, ActiveSync was replaced with Windows Mobile Device Center. Device Center is included with Vista and Windows 7 and contains the same functionality of its predecessor. This new version provides many front end enhancements, allowing a home user to sync PIM information with Microsoft Outlook 2003 and later, photos from Windows Photo Gallery, videos or music from Windows Media Player and favorites with Internet Explorer; without the need for a server back end. Devices at this time also included a base driver compatible with Mobile Device Center so a user can connect to a computer without a need for any configuration.

mobile phones

A mobile phone (also known as a cellular phone, cell phone, and a hand phone) is a device that can make and receive telephone calls over a radio link while moving around a wide geographic area. It does so by connecting to a cellular network provided by a mobile phone operator, allowing access to the public telephone network. By contrast, a cordless telephone is used only within the short range of a single, private base station.

In addition to telephony, modern mobile phones also support a wide variety of other services such as text messaging, MMS, email, Internet access, short-range wireless communications (infrared, Bluetooth), business applications, gaming and photography. Mobile phones that offer these and more general computing capabilities are referred to as smartphones.


Mobile technology

Mobile technology is the technology used for cellular communication. Mobile code division multiple access (CDMA) technology has evolved rapidly over the past few years. Since the start of this millennium, a standard mobile device has gone from being no more than a simple two-way pager to being a mobile phone, GPS navigation device, an embedded web browser and instant messaging client, and a handheld game console. Many experts argue that the future of computer technology rests in mobile computing with wireless networking. Mobile computing by way of tablet computers are becoming more popular. Tablets are available on the 3G and 4G networks.


Pager

A pager is a wireless telecommunications device that receives and displays numeric or text messages, or receives and announces voice messages. One-way pagers can only receive messages, while response pagers and two-way pagers can also acknowledge, reply to, and originate messages using an internal transmitter. Pagers operate as part of a paging system which includes one or more fixed transmitters (or in the case of response pagers and two-way pagers, one or more base stations), as well as a number of pagers carried by mobile users. These systems can range from a restaurant system with a single low-power transmitter, to a nationwide system with thousands of high-power base stations.

One of the first practical paging services was launched in 1950 for physicians in the New York City area. Physicians paid US$12 per month for the service and carried a 200 gram (6 oz) pager that would receive phone messages within 40 km (25 mi) of a single transmitter tower. The system was manufactured by the Reevesound Company and operated by Telanswerphone. In 1960, John Francis Mitchell combined elements of Motorola's Walkie Talkie and automobile radio technologies to create the first transistorized pager, and from this point, paging technology continued to advance, and pager adoption continued to expand, until the early 1990s. However, by the mid-1990s, as cellular technologies became cheaper and more widely available, advanced services began to displace paging as a commercial product. Today, pagers exist largely as niche products, finding preferential use in applications such as hospitals, public safety, and retail locations where their simplicity, high reliability, and low cost represent significant advantages.

In computer telecommunication, the Hayes command set is a specific command language originally developed for the Hayes Smartmodem 300 baud modem in 1981. The command set consists of a series of short text strings which combine together to produce complete commands for operations such as dialing, hanging up, and changing the parameters of the connection. The vast majority of dialup modems use the Hayes command set in numerous variations.

The command set covered only those operations supported by the earliest 300 bit/s modems. When new commands were required to control additional functionality in higher speed modems, a variety of one-off standards emerged from each of the major vendors. These continued to share the basic command structure and syntax, but added any number of new commands using some sort of prefix character - & for Hayes and USR, \ for Microcom, for instance. Many of these re-standardized on the Hayes extensions after the introduction of the SupraFAXModem 14400 and the subsequent market consolidation that followed.


Telephone numbers

A telephone number is a unique sequence of digits assigned to each telephone subscriber station, telephone line, or since the advent of digital telephony to an electronic telephony device, such as a mobile telephone. The telephone number serves as the address to switch telephone calls using a system of destination routing. It is entered or dialed by the calling party on the originating telephone set which transmits it in the process of signaling to a telephone exchange which completes the call either to another locally connected subscriber or via the public switched telephone network (PSTN) to the called party.

The concept of using telephone numbers instead of subscriber names when connecting calls was developed and first used between 1879 and 1880 in Lowell, MA, for the purpose of ease of training new telephone operators.

Technology
Radio paging

A pager is a wireless telecommunications device that receives and displays numeric or text messages, or receives and announces voice messages. One-way pagers can only receive messages, while response pagers and two-way pagers can also acknowledge, reply to, and originate messages using an internal transmitter. Pagers operate as part of a paging system which includes one or more fixed transmitters (or in the case of response pagers and two-way pagers, one or more base stations), as well as a number of pagers carried by mobile users. These systems can range from a restaurant system with a single low-power transmitter, to a nationwide system with thousands of high-power base stations.

One of the first practical paging services was launched in 1950 for physicians in the New York City area. Physicians paid US$12 per month for the service and carried a 200 gram (6 oz) pager that would receive phone messages within 40 km (25 mi) of a single transmitter tower. The system was manufactured by the Reevesound Company and operated by Telanswerphone. In 1960, John Francis Mitchell combined elements of Motorola's Walkie Talkie and automobile radio technologies to create the first transistorized pager, and from this point, paging technology continued to advance, and pager adoption continued to expand, until the early 1990s. However, by the mid-1990s, as cellular technologies became cheaper and more widely available, advanced services began to displace paging as a commercial product. Today, pagers exist largely as niche products, finding preferential use in applications such as hospitals, public safety, and retail locations where their simplicity, high reliability, and low cost represent significant advantages.


Electronic engineering

Electronics engineering, or electronic engineering, is an engineering discipline where non-linear and active electrical components such as electron tubes, and semiconductor devices, especially transistors, diodes and integrated circuits, are utilized to design electronic circuits, devices and systems, typically also including passive electrical components and based on printed circuit boards. The term denotes a broad engineering field that covers important subfields such as analog electronics, digital electronics, consumer electronics, embedded systems and power electronics. Electronics engineering deals with implementation of applications, principles and algorithms developed within many related fields, for example solid-state physics, radio engineering, telecommunications, control systems, signal processing, systems engineering, computer engineering, instrumentation engineering, electric power control, robotics, and many others.]verification needed[

The Institute of Electrical and Electronics Engineers (IEEE) is one of the most important and influential organizations for electronics engineers.

Social Issues Technology Internet
Human Interest

In journalism, a human interest story is a feature story that discusses a person or people in an emotional way. It presents people and their problems, concerns, or achievements in a way that brings about interest, sympathy or motivation in the reader or viewer.

Human interest stories may be "the story behind the story" about an event, organization, or otherwise faceless historical happening, such as about the life of an individual soldier during wartime, an interview with a survivor of a natural disaster, a random act of kindness or profile of someone known for a career achievement.

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