Disco was not an original studio album, but rather a collection of remixes of tracks from their first album, Please, and its respective B-sides. Many fans of 1980s synthpop view the mixes on this album as some of the best examples of the extended dance mix, and this album includes remixes by Arthur Baker, Shep Pettibone and Pet Shop Boys themselves.
It is difficult to say where Pet Shop Boys saw this album fitting in among their other albums when they released it. In 2001, when they re-released what they deemed their first six albums, Disco was not included.
In addition, Pet Shop Boys would later release the remix albums Disco 2, Disco 3 and Disco 4, although the concepts of these compilations differ greatly from the original Disco album: Disco 2 is a continuous mega-mix of dance remixes, Disco 3 is a mixture of remixes and new songs and Disco 4 consists exclusively of tracks remixed by the Pet Shop Boys, mainly by other artists.
The sleeve cover was a still of Chris Lowe from the promo video of "Paninaro" directed by the Pet Shop Boys themselves.
The Disco mixes of "Suburbia" and "Paninaro" can also be found on the "Suburbia" 12" and the 2001 two-disc re-release of Please. 7" versions of both mixes of these songs were used for the "Suburbia" single release.
The original version of "In the Night" was the B-side to the original release of "Opportunities (Let's Make Lots of Money)". Arthur Baker's Extended Mix of "In the Night" was used as the theme for the BBC's The Clothes Show. In the mid-1990s, the Pet Shop Boys remixed "In the Night" again in a then-contemporary style so that the programme would continue to use the theme. This version, known as "In the Night 1995", was released as a B-side to the 1996 single "Before" and was then collected on the 2001 two-disc re-release of Bilingual.
American music reviewer Robert Christgau referred to Shep Pettibone (who mixed Pet Shop Boys's biggest hit, "West End Girls") as 'Pet Sheppibone' in his review.