Big Brother is the nominal leader of the political system that is described in George Orwell's novel "1984".
"Big Brother" is a dictator in a totalitarian state, taken to its utmost logical consequence. In the society that Orwell describes, everybody is under complete surveillance by the authorities. The people are constantly reminded of this by the phrase "Big Brother is watching you", which is the core "truth" of the propaganda system in this state.
The physical description of "Big Brother" is reminiscent of Joseph Stalin. In the novel, it is not clear if he actually exists as a person, or is an image crafted by the state.
A reality television show in which a number of people are secluded in a house with cameras able to view their activities from every angle. At regular intervals, one of the contestants is voted off the show. The first edition was broadcasted in The Netherlands in 1999.
See also: Big Brother television program, Survivor