In early 1973 British experimental rock band Pink Floyd released their 8th album, Dark Side of the Moon, arguably the greatest rock album ever created. Since its release, it has become a cornerstone to 20th century culture and provided great inspiration to artists within and outside of music. Its success encouraged other musicians to explore more progressive styles of music, and it raised the bar for recorded sound for future albums.
The hard work that Pink Floyd put into this album paid off financially as Dark Side of the Moon became one of the best-selling albums of all time. After its release it went to number one on the Billboard chart for one week, but it ended up staying on the Billboard charts for a consecutive 741 weeks (or just over 14 years). This feat would make the album one of the Top 25 best-selling albums ever.
Dark Side of the Moon has endured through the years because it is such a well written and thought out concept album. A concept album is an album where all (or most) of the songs on that album revolve around a story or a theme. This is a contrast to most studio albums which just lay out a series of songs that are often unconnected or unrelated with the exception of the fact that they are on the same album.
Knowing that Dark Side of the Moon is a concept album has given rise to a number of theories about what the album's concept is, and or, what the meaning of the album is. The band has given partial explanations to some of the songs and the album as a whole, but for the most part they have left it up to listeners to decide for themselves.
In a nutshell, Dark Side of the Moon is a concept album that discusses the philosophical and physical ideas that can lead to a person's insanity, and ultimately an unfulfilled life.