Pink Floyd pushed the envelope in the mid-'60s and '70s with a cosmic sound that rolled reverb, screech, and feedback into both long instrumental arpeggios and memorable rock anthems. The group began in London, England, led initially by virtuoso singer/guitarist Syd Barrett, fleshed out by bassist Roger Waters, keyboardist Richard Wright, and drummer Nick Mason. Their live-on-tour combination of soulful lyrics and palpable melody backed by psychedelic light shows rocked fellow Brits and guaranteed blockbuster status for their debut album, The Piper at the Gates of Dawn, released in 1967. Genius and madman stand cheek by jowl on the scale of creativity, however, and Barrett, already unstable, began a descent into darkness that made him and his music even more unconventional and boundary-defying. He departed the group, leaving Waters and new guitarist David Gilmour to switch off on vocals, and the maniacal foundation of the band was anchored by the new band dynamic.
Their next few releases fared very well in the UK: 1968's A Saucerful of Secrets sold well and marked a sonic shift towards a spacier, more orchestral sound, and their release the following year, Ummagumma, featured both live material and studio recordings. They released three more records in this ethereal, more cerebral domain: More… (a film soundtrack), Atom Heart Mother, and Meddle, the last of which saw them slide into more accessible domain. Over time, Waters would emerge as the band's next leading visionary, and Pink Floyd's seismic 1973 album Dark Side of the Moon broke them big-time into the American market, spending an enormous length of time on the charts and ensuring them a permanent place on classic rock radio with such eccentric hits as "Money" and "Time."
Two years later, they released the similarly acclaimed (but far more subdued) record Wish You Were Here, a record that partly took a nostalgic look backwards at Barrett's tenure in the band—a fascination that would be expanded upon considerably with the release of The Wall at the end of the decade. 1977's Animals is an interesting, anomalous entry in their catalog, taking a very dark view of mankind and the modern era with its extended, inward-gazing instrumentals and its hopeless lyrics. The Wall followed in '79, a hit with fans if not their critics, due in part to its lighter, more pop-oriented sound and its epic-scale melodrama. "Another Brick in the Wall" would become perhaps their most iconic song, and the record's accompanying tour entailed the construction (and subsequent knocking over) of an actual wall onstage as the band performed.
Following 1983's The Final Cut, a less well-received record that was effectively a Waters solo release, Waters departed the band due to personal tensions and a lawsuit filed over the group's partnership. Momentary Lapse of Reason in '87 and The Division Bell in '94 were successful, post-Waters releases, demonstrating that the band could muster a good enough facsimile of their cutting-edge genre to please both devotees of their early music and a new generation of younger fans. Waters would continue as a solo artist, and Syd Barrett, who released two notable 1970 solo records—The Madcap Laughs and Barrett—passed away in 2006 at the age of 60 after years of seclusion in his Cambridge home.