When people ask Elon Musk how he learned to build rockets, he has a simple answer.

"I read books," he reportedly likes to say.

Musk — who was smart enough to get into a physics Ph.D. program at Stanford University and then drop out because it didn't seem that relevant to him — has always been hungry for the written word.

In its profile of the Tesla and SpaceX CEO, The New Yorker observed that he was picked on a lot during his South African childhood, and he would retreat into fantasy (J.R.R. Tolkien) and science-fiction (Isaac Asimov) to cope.

As we'll see below, books have always been important to Musk: inspiring him as a child, giving him heroes as a young adult, and helping him to learn rocket science while launching SpaceX.