The mail or post is a system for physically transporting documents and other small packages, as well as a name for the postcards, letters, and parcels themselves. A postal service can be private or public, though many governments place restrictions on private systems. Since the mid-19th century national postal systems have generally been established as government monopolies with a fee on the article prepaid. Proof of payment is often in the form of adhesive postage stamps, but postage meters are also used for bulk mailing. Modern private postal systems are typically distinguished from national postal agencies by the names "courier" or "delivery service".
Postal authorities often have functions other than transporting letters. In some countries, a Postal Telegraph and Telephone (PTT) service oversees the postal system as well as having authority over telephone and telegraph systems. Some countries' postal systems allow for savings accounts and handle applications for passports.
In computing, cross-platform, or multi-platform, is an attribute conferred to computer software or computing methods and concepts that are implemented and inter-operate on multiple computer platforms. Cross-platform software may be divided into two types; one requires individual building or compilation for each platform that it supports, and the other one can be directly run on any platform without special preparation, e.g., software written in an interpreted language or pre-compiled portable bytecode for which the interpreters or run-time packages are common or standard components of all platforms.
For example, a cross-platform application may run on Microsoft Windows on the x86 architecture, Linux on the x86 architecture and Mac OS X on either the PowerPC or x86 based Apple Macintosh systems. A cross-platform application may run on as many as all existing platforms, or on as few as two platforms.
Web 2.0 describes web sites that use technology beyond the static pages of earlier web sites. The term was coined in 1999 by Darcy DiNucci and was popularized by Tim O'Reilly at the O'Reilly Media Web 2.0 conference in late 2004. Although Web 2.0 suggests a new version of the World Wide Web, it does not refer to an update to any technical specification, but rather to cumulative changes in the way web pages are made and used.
A Web 2.0 site may allow users to interact and collaborate with each other in a social media dialogue as creators of user-generated content in a virtual community, in contrast to websites where people are limited to the passive viewing of content. Examples of Web 2.0 include social networking sites, blogs, wikis, folksonomies, video sharing sites, hosted services, web applications, and mashups.
The United States Postal Service (USPS), also known as the Post Office and U.S. Mail, is an independent agency of the United States federal government responsible for providing postal service in the United States. It is one of the few government agencies explicitly authorized by the United States Constitution. The USPS traces its roots to 1775 during the Second Continental Congress, where Benjamin Franklin was appointed the first postmaster general. The cabinet-level Post Office Department was created in 1792 from Franklin's operation and transformed into its current form in 1971 under the Postal Reorganization Act.
The USPS employed 522,144 workers and operated 212,530 vehicles in 2012. The USPS is the operator of the largest civilian vehicle fleet in the world. The USPS is legally obligated to serve all Americans, regardless of geography, at uniform price and quality. The USPS has exclusive access to letter boxes marked "U.S. Mail" and personal letterboxes in the United States, but still competes against private package delivery services, such as UPS and FedEx.