Simply the best pianist of all time. He was incredibly innovative, wore a beret and sunglasses at most of his performances. Showed emotion, used complex rhythms, and was awesome.
Monk is in the ranks with Duke Ellington, Oscar Peterson, Art Tatum, Bill Evans, etc.
Person A: You haven't heard of Thelonious Monk?
Person B: No, who's he?
Person A: You're retarded.