Ask HN: Books that made you fascinated to learn more mathematics?

What are some mathematics books that made you so fascinated about the subject that you became curious and started learning more and ultimately became a student of mathematics directly or indirectly?

The books got you from understanding mathematics as rote arithmetic calculations to what mathematics really is about. Of course the books were themselves good teachers due to their excellent exposition and carefully set exercise problems (maybe with solutions).

Btw, I am not talking only about pure mathematics.

Do you have a few such books?