Format is a double-disc compilation album of B-sides from various singles released by the Pet Shop Boys from 1996–2009 (Bilingual through Yes, or "Before" to "Did You See Me Coming?"). It is their second B-sides album after Alternative, which was released in 1995 and collected B-sides from the time of their first single release "West End Girls" (1985) through 1994 ("Yesterday, When I Was Mad"). The album's release was initially announced in November 2011, then officially on 19 December 2011 through the Pet Shop Boys' official website, offering it for pre-order. The album was released on 6 February 2012 in the UK, but was released earlier in various territories worldwide, including Australia, where it was released on 3 February.