Human behavior refers to the range of behaviors exhibited by humans and which are influenced by culture, attitudes, emotions, values, ethics, authority, rapport, hypnosis, persuasion, coercion and/or genetics.
The behavior of people (and other organisms or even mechanisms) falls within a range with some behavior being common, some unusual, some acceptable, and some outside acceptable limits. In sociology, behavior in general is characterised as having no meaning, being not directed at other people, and thus is the most basic human action. Behavior in this general sense should not be mistaken with social behavior, which is a more advanced action, as social behavior is behavior specifically directed at other people. The acceptability of behavior depends heavily upon social norms and is regulated by various means of social control. Human behavior is studied by the specialised academic disciplines of psychiatry, psychology, social work, sociology, economics, and anthropology.
A bar joke is a very common and basic type of joke. The basic syntax of this type of joke is "A man walks into a bar and <something happens here>". The initial perception of the joke is that a man is walking into a bar to have a drink, but this only lasts a few seconds as the punchline is quickly uttered. This joke has gained an incredible amount of variants over the years. It is often used by comedians, and people telling jokes to friends.
The bar joke has a large number of variations. The types of variations include puns or word plays (the man walks into a bar and pulls out a tiny piano and a 12-inch pianist, followed by any number of different punchlines; or man with dyslexia walked into a bra), or replace the man with woman, a famous person, people of various occupations, animals (a duck walks into a bar, orders a beer, and tells the bartender, put it on my bill) or inanimate objects (a sandwich walks into a bar, orders a beer, and is told by the bartender, we don't serve food here). Sometimes the unexpected happens: "A man walks into a bar. Ouch!"