E4 is a British digital television channel launched as a companion to Channel 4 in January 2001. The "E" officially stands for entertainment (although it can also be seen as a sly reference to the drug Ecstasy), and the channel is mainly aimed at the lucrative 18 - 35 age group. Programming includes US imports such as Friends, ER, The Sopranos, Six Feet Under and The West Wing, sometimes premiering on E4 before being broadcast on Channel 4, plus lots of home-grown chat and reality shows.

Every year, whilst the Big Brother television programme airs, E4 cancels almost all other programmes, and the channel's schedule is devoted almost entirely to by Big Brother programing such as live coverage from inside the Big Brother house, interactive features that give access to additional camera angles within the house, Big Brother voting options and (ironically) Big Brother "catch up" shows (i.e., repeats).