33+1⁄3 is a series of books, each about a single music album. The series title refers to the rotation speed of a vinyl LP, 33+1⁄3 RPM.

Unknown Pleasures is the debut studio album by the English rock band Joy Division, released on 15 June 1979 by Factory Records. The album was recorded and mixed over three successive weekends at Stockport's Strawberry Studios in April 1979, with producer Martin Hannett contributing a number of unconventional recording techniques to the group's sound. The cover artwork was designed by artist Peter Saville, using a data plot of signals from a radio pulsar. It is the only Joy Division album released during lead singer Ian Curtis's lifetime.