Please answer the following question: Disco 4 also known as Disco Four is the eighteenth album by the UK electronic music duo Pet Shop Boys and the fourth in the band's Disco series. It was released on 8 October 2007 on compact disc and vinyl. It was not released on digital download due to licensing difficulties for each track.The album is mainly a compilation of Pet Shop Boys remixes of songs by other artists a first among any of their releases to date. Given a list of categories: company, educational institution, artist, athlete, office holder, mean of transportation, building, natural place, village, animal, plant, album, film or written work, what category does the paragraph belong to?
Answer:
Album