Keith Moon was the drummer in the English rock band The Who. From what I have heard and seen he seems to be a bit crazy, but his abilities on the drums are simply amazing. He's swinging his arms around, hitting his drums as fast as few people can do it, making jokes on stage, fooling around off stage.
I have to agree with StopTheViolins that Keith Moon was a very, very great drummer, but I have to admit that I don't know as much about music as other people may know, so I won't say he's the best.
If you want to know, why we think that he was so good, then get some live records from The Who (e.g. Heaven And Hell from Live At Leeds) and listen to Keith's drumming style.
He was a wild person, destroying drum kits and hotel rooms after Who shows, but also a funny guy (listen to Keith's comments to Pete's talk about A Quick One (While He's Away) from Live At Leeds). It's sad that he took too many drugs and drunk a bit too much.
Keith Moon was born on August 23, 1946 (thanks Layla), in Wembley, London. Even when he was young, he was simply Keith Moon-like, supposedly one of his teachers has written the following about him: "Retarded artistically, idiotic in other respects."
As a young man, Keith played in a band, the Beachcombers, a surf music group. Keith liked that kind of music and also groups like the Beach Boys. At the same time, in the same town, a young band, called the Detours, had problems with their drummer Doug Sandom, who left the band. After that the Detours had a drummer, who played with them at their shows. At one such gig, a drunk man approached the group and told them he had a friend, who was a much better drummer than their current substitute.
Some days later Keith played a few songs with the band, which were The Who by now, and became their new drummer. He was wondering if leaving the Beachcombers and joining The Who, who had a very bad reputation, was a good idea, but he did it nevertheless, because the Who was a better band. Keith was 18 at that time.
John and Keith would become the very close friends, but Keith had some problems with Roger. He told him he couldn't sing, because he didn't like many of the Who's records. Perhaps that's why Roger once flushed Keith's pills and knocked him out after Keith attacked him. The Who solved this problem by kicking out Roger and bringing him back in again, after he promised that he would be more peaceful.
At this time (1965) Keith and Pete were already smashing their equipment after their shows. Probably the most famous act of destroying his drums was at the Smothers Brothers show, when he had explosives in his bass drum that exploded during "My Generation". Keith got a piece of a cymbal into his leg and Pete temporarily lost his hearing; arguably his later hearing problems are from this show, too.
When he wasn't recording our touring with The Who, Keith used to be at parties, drinking, and taking pills. He often smashed hotel rooms, when he was touring, and got banned from pubs and restaurants. He enjoyed dressing up, e.g. as Adolf Hitler, Santa Claus, etc.
Of course, this lifestyle began to take its toll on him physically. His heavy drug usage made him look fatter and older than he really was. He did, however, try to get a bit cleaner and cut back his drinking. It didn't help much, so on September 7, 1978, he died in London after taking too many of his prescription pills (32). He was 32 years old.
Rock music had lost one of its greatest drummers.