Richard Wright co-wrote a number of tracks on the album Dark Side of the Moon
By Ian Youngs
Music reporter, BBC News
As a keyboardist and songwriter, Richard Wright helped create the pioneering psychedelic sound that made Pink Floyd one of the world's greatest groups.
His atmospheric, jazzy organs and synthesisers were at times at the forefront of their songs, and at others provided a dreamy undercurrent upon which the rest of the band could drift.
Wright was studying architecture at the Regent Street Polytechnic in London when he met fellow students Nick Mason and Roger Waters.
They formed the Architechtural Abdabs in 1965, before art student Syd Barrett joined and the group became Pink Floyd.
Wright (right) and the band were central figures in swinging London
They made their names on London's artistic underground scene, "playing music which the record companies could not understand", as Wright later put it.
"We never had a desire to be famous, to be rock 'n' roll stars," he said.
The musical style of jazz greats like Miles Davis influenced his keyboard playing the most, he said.
Barrett was the leading creative force in the early days, but drug use soon led to his mental deterioration.
The rest of the band, though, did not partake in heavy drug use.
Wright took two acid trips - one before he was in the band, which was "quite enjoyable", and a more unpleasant experience that put him off for life.
"It's a mistake thinking that drugs supplied Pink Floyd with the inspiration," he said.
"The ones who took drugs were the ones who came to see the shows."
After Barrett left, and with new guitarist Dave Gilmour on board, the band started to redefine themselves in the late 1960s and early '70s, moving away from eccentric pop to prog rock.
As well as providing backing vocals and keyboards, Wright wrote some of their songs.
They included the instrumental 13-minute Sysyphus on 1969's Ummagumma and Summer '68 from Atom Heart Mother, their first number one album.
The 23-minute Echoes, from their next long player, Meddle, centred around a single Wright piano note.
Their following release, 1973's Dark Side of the Moon, was their masterpiece.
Wright co-wrote much of the album, including Breathe, Time and Us and Them, but his most significant contribution was the piano-led The Great Gig in the Sky.
The album is one of the best-selling albums of all time and stayed in the US top 200 for 15 years.
The group became one of the biggest groups of the 1970s, and continued releasing albums, while Wright also branched out with a solo career.
Gilmour (left), Mason (centre) and Wright carried on into the 1990s
But band relations were deteriorating, and Waters effectively sacked Wright after the 1979 album The Wall.
Waters had threatened to withhold the album if Wright refused to quit, the keyboardist later said.
"There was this big personality clash between me and Roger, and at the end of the day I realised that I couldn't work with this person anyway - so I left."
The other band members also fell out with Waters, with Gilmour and Mason starting work on a new Pink Floyd album without him in 1986.
Wright rejoined the splinter group as they continued to record and tour as Pink Floyd - after a lengthy legal battle with Waters.
They made two more Pink Floyd albums and played more than 100 shows on the Division Bell tour in 1994, the most lucrative tour in rock history at that time.
After that, the group fell dormant. Wright released another solo album and let off steam on his 65-foot yacht in the Virgin Islands.
Sailing was his "therapy and it releases all the pressures that one does get in this business", he said.
He joined his former bandmates, with the exception of Barrett, one last time at Live 8 in Hyde Park in 2005.
There has since been continual speculation that the group could reform to tour again.
But with Wright's passing, a hugely important chapter in the story of British music has closed.