I used this 119 page book to get up to speed on using my new TI-84 calculator. I found it enjoyable reading, with easy to understand examples, and I went through the book in about two weeks doing all the examples. It was an enjoyable educational experience and probably much more efficient than trying to dig the information out of the TI's big 458 page manual. Carl Swenson's book starts with the "on" key at page 1 and goes progressively through the uses of the calculator up to and including graphing solutions for differential equations, and finishes in slightly over a hundred pages. Even if a person hasn't had calculus yet, he or she can start on page one and work through the book up to the point where their mathematical understanding ends. For anyone that has a TI-84 or 83 calculator and wants to understand how to use it, I strongly recommend this book.