I'm not a sci fi reader, but those who love the stuff know he's the author of more than 100 books - now that's prolific - and the co-creator of 2001: A Space Odyssey, a movie I have never quite figured out the appeal of but that sci fi fans of all shapes and sizes and ages adore. (What's up with those apes at the beginning? I mean, what the hell?) Still, I believe I did read a short story by him in high school which may or may not have been called The Nine Billion Names of God, and from what I remember it was pretty good.
If any sci fi readers could put him in proper perspective, I'd be grateful.