Asimov was a very versatile writer. I don't think there are many science-fiction readers who've never read stories by him. However, he wrote much more than just the science-fiction short stories and novels. Here's a sample and I make no claims that it's complete:

1. Straight fantasy stories such as the "George and Azazel" stories, many of which are anthologized in "Magic."

2. Chemistry textbooks.

3. At least two books on humor.

4. A two-volume Guide to the Bible (written by an atheist whose parents were Russian Jews it should make for interesting reading for anyone, Judeo-Christian or not).

5. Numerous non-fiction articles on just about anything in the Universe (environment, writing, feminism, the computerization of society, etc. etc. etc.).

6. He's also helped edit many anthologies, both of his own works and that of other authors.