If you owned a television set in the 70s or early 80s, it's likely that the third and fourth buttons were marked 'ITV1' and 'ITV2'. In the event, the channel that everyone had expected to be called 'ITV2' instead launched under the name Channel 4 (except for viewers in Wales who had their own channel, S4C).
It took until the advent of digital television for a channel bearing the name ITV2 to launch, as the first ITV-branded spin-off channel. Launching on 7th December 1998, it was initially not available to satellite viewers, in order to generate interest in the Granada and Carlton-owned terrestrial subscription service, OnDigital. Viewers in Scotland received a spin-off channel from STV, known as S2, in place of ITV2 until 2001, while those in Northern Ireland received UTV2 (originally known as TV You) until 2002.
ITV2 has grown to become one of the most successful multichannels, making a name for itself with the likes of The Only Way is Essex and Love Island.
Its most recent ident package was introduced in August 2015, and is comprised of a series of quirky short clips which are randomly sequenced together live on transmission. This method is said to create more than 300,000 possible permutations, so it's unlikely the exact same sequence will ever be seen on air more than once.