What is Pink Floyd's most famous and iconic album?

There are HIT albums, and then there’s The Dark Side of the Moon. Pink Floyd‘s eternally popular song cycle has sold more than 15 million copies in the U.S. since its release on March 1st, 1973, and more than 45 million units worldwide. A true colossus of classic rock, the album made its creators — bassist/vocalist Roger Waters, guitarist/vocalist David Gilmour, keyboardist/vocalist Rick Wright, and drummer Nick Mason. In addition to its massive commercial success, Dark Side of the Moon was also a career-defining artistic achievement for the British quartet, one which marked Pink Floyd’s transition from an experimental, jam-oriented progressive outfit primarily beloved by college students and assorted “heads”.

Source: Rolling Stone