Most of the time, the thing that really helps you to learn something is a great teacher. When you have a teacher that is, for whatever reason, not able to impart the concepts to you in a way that makes sense you can get frustrated. I like this book because it's written by a funny, great teacher who can be a substitute for a less than dynamic teacher. The examples are good, the language is humorous and memorable. It breaks down concepts in a way that's easy to digest. It's not a replacement for a calculus textbook (it doesn't intend to be), but it is well constructed. The only thing it doesn't have are example problems for you to work out, like a textbook does.