One book that I am grateful for. (Just one? Really? Fine)
Harry Potter and the Prisoner of Azkaban by J.K Rowling:
This is the first book (aside from the many books by Dr. Seuss) that I read. No I didn't start with the first book in the Harry Potter series, I started with this one. This book opened my eye to the possibility of exactly WHAT a book could do for you. It was the door way to so many other books, so I thank it for that.