Albums of recorded music were developed in the early 20th century, first as books of individual 78rpm records, then from 1948 as vinyl LP records  played at  rpm. Vinyl LPs are still issued, though in the 21st century albums sales have mostly focused on compact disc (CD) and MP3 formats. The audio cassette was a format used in the late 1970s through to the 1990s alongside vinyl.

Albums of recorded music were developed in the early 20th century, first as books of individual 78rpm records, then from 1948 as vinyl LP records  played at  rpm. Vinyl LPs are still issued, though in the 21st century albums sales have mostly focused on compact disc (CD) and MP3 formats. The audio cassette was a format used in the late 1970s through to the 1990s alongside vinyl.