The Dark Side of the Moon is the 8th album by English rock band Pink Floyd. It was released on March 1, 1973, by Harvest Records and it was built on ideas explored in earlier recordings and live shows. Its themes look at conflict, greed, the passage of time and mental illness, the last theme being primarily inspired by the deteriorating mental state of the founding member and principal contributor, Syd Barrett. Take a look below for 23 more interesting and fascinating facts about Pink Floyd’s The Dark Side of the Moon.

1. The album was developed during live performances and an early version was premiered several months before recording even began.

2. Pink Floyd used advanced recording techniques at the time, including multitrack recording and tape loops. Also, analogue synthesizers were used in several tracks, as well as snippets from recorded interviews with Pink Floyd’s road crew.

3. Engineer Alan Parsons was responsible for many distinctive sonic aspects as well as the recruitment of singer Clare Torry.

4. The album’s iconic cover art was designed by Storm Thorgerson with keyboardist Richard Wright’s request for something simple and bold. The art depicts a prism spectrum, representing the band’s lighting and the albums themes.

5. The album is estimated to have sold 45 million copies, making it Pink Floyd’s most successful album and one of the best selling albums worldwide.

6. The Dark Side of the Moon has been remastered and re-released several times, and covered in its entirety by several acts.

7. The album is known for its use of musique concrete and conceptual, philosophical lyrics, as found in a lot of the band’s other work.

8. Each side of the album is a continuous piece of music. The five tracks on each side reflect various stages of human life, beginning and ending with a heartbeat.

9. The album was recorded at Abbey Road Studios, in two sessions, between May, 1972, and January, 1973. The band was assigned staff engineer Alan Parsons, who had worked as an assistant tape operator on Atom Heart Mother, and who had gained experience as a recording engineer on the Beatles’ Abbey Road and Let It Be.

10. Beginning on June 1, the first track to be recorded was “Us and Them,” followed by “Money” six days later.

11. Waters created effects loops from recordings of various money related objects, such as coins being thrown into a food mixing bowl taken from his wife’s pottery studio.

12. Their recording sessions were regularly interrupted, sometimes by Waters breaking to see his favorite team, Arsenal F.C., compete. Sometimes the band would also stop to watch Monty Python’s Flying Circus on the TV, leaving Parsons to work on material recorded up to that point.

13. The prism design on the album cover was inspired by a photograph that Thorgerson had seen during a brainstorming session with Powell.

14. The artwork was created by their associate, George Hardie. Hipgnosis offered the band a choice of several designs, but all four members agreed that the prism was by far the best.

15. The design represents three elements, the first is the band’s stage lighting, the second is the album’s lyrics, and the third is Wright’s request for a simple and bold design.

16. The gatefold design also included a visual representation of the heartbeat sound used throughout the album, and the back of the album cover had Thorgerson’s suggestion of another prism recombining the spectrum of light.

17. Waters was credited as the author of the album’s lyrics, making The Dark Side of the Moon the first of five consecutive Pink Floyd albums with lyrics credited to him alone.

18. The band was so confident in the quality of the lyrics that, for the first time, they printed them on the album’s sleeve.

19. The Dark Side of the Moon was released first in the United States on March 1, 1973, and then in the United Kingdom on March 16. It became an instant chart success in Britain and throughout Western Europe.

20. A lot of the album’s early American success is attributed to the efforts of Pink Floyd’s U.S. record company, Capitol Records. The newly appointed chairman Bhaskar Menon set about trying to reverse the relatively poor sales of the band’s 1971 studio album Meddle.

21. The success of the album brought a lot of money to all four members of the band. Richard Wright and Roger Waters bought big country houses, and Nick Mason became a collector of upmarket cars. Some of the profits were also invested in the production of Monty Python and the Holy Grail.

22. Engineer Alan Parsons received a Grammy Award nomination for Best Engineered Recording, Non-Classical for The Dark Side of the Moon. He went on to have a successful career as a recording artist with the Alan Parsons Project.

23. The Dark Side of the Moon frequently appears on rankings of the greatest albums of all time. In 1987, Rolling Stone listed the album as 35th on its Top 100 Albums of the Last 20 Years.