Paul Desmond (1924-1977) was a jazz alto saxophonist, most well known for his contributions to the quartet of Dave Brubeck, and for penning the very well known hit Take Five for the group. However, he was a supremely talented musician who earned the respect of peers such as Charlie Parker, and who made a number of fine recordings with other jazz notables such as Jim Hall, Gerry Mulligan and Chet Baker.

Desmond was creatively at his peak in the 1950's, a decade most known for the development of bebop, in jazz terms. However, his style was much more relaxed and obviously melodic than most of the boppers, and he never really embraced the style. His primary influence was probably the great tenor saxophonist Lester Young from the generation before. His improvisations are characterised by long, flowing lines full of melodic invention, and a gentle and relaxed tone that worked exceptionally well in the piano-less quartet he shared with Jim Hall. With his sophisticated and elegant approach, his sound was perhaps the epitomy of cool jazz, as it came to be known (though I don't know of him using that description himself).

He was something of a wit, often making self-deprecating comments about his playing ("I tried practicing for a few weeks and ended up playing too fast"), or his lifestyle ("Sometimes I get the feeling that there are orgies going on all over new York City, and somebody says, `Let's call Desmond,' and somebody else says, 'Why bother? He's probably home reading the Encyclopedia Britannica'"). He had in fact studied creative writing, and wrote a funny article for Punch on touring with the Brubeck quartet. You can find some of his writings and quotes by visiting the links below.

Desmond was a heavy smoker and a drinker, and apparently also dabbled in harder drugs, but it was cigarettes that did most damage, it seems. He passed away in 1977 from lung cancer.

Reading:
wikipedia
puredesmond.ca
an interesting bio

Recommended listening:
If you didn't already hear it, I guess "Take Five" with Brubeck, also "Blue Rondo a la Turk" and other recordings.
"Take Ten" with Jim Hall, Percy Heath and Connie Kay, or any other work with these musicians - there are many compilations.