The Crochet Answer Book, by Edie Eckman, uses a question and answer format to present a lot of information in a compact size. Subtitled "Solutions to Every Problem You'll Ever Face; Answers to Every Question You'll Ever Ask", the book includes many of the crochet questions you are likely to have. A beginning or intermediate crocheter will find much helpful information.
The book is divided into 11 chapters including: hooks and other tools, a good yarn, strong foundations, in stitches, tense about gauge, going in circles, a whole cloth, pattern language, on the edge, the finish line and something different. A resources section in the back of the book gives suggestions on finding other crocheters and crocheting resources and has a few useful, informative websites.
"The Crochet Answer Book" is 4½ by 6½ by 1 inch thick, a nice size to carry with your crochet. If you have no crochet experience, you may want to get or borrow a book or video with basic how-to-crochet instructions. The stitch diagrams and instructions in "The Crochet Answer Book" are as good as those in most pattern books, so if you learn easily from books they may be all you need. Once you've made that first scarf or dishcloth, this book can answer your questions and help you learn the finer points of crochet.
This book has good information on marking stitches, finishing your work, how many increases you need to make a flat circle or square, and more. There is detailed information on reading patterns, covering both abbreviations and stitch diagrams.
There is such a variety of crochet stitches and stitch patterns, it is impossible to give detailed information on all aspects of crochet in a book this size. A few of the answers were disappointing. For example, in discussion Tunisian crochet (afghan stitch), the question: "Can I work stitch patterns in Tunisian crochet?" is asked. The answer: "Absolutely!" plus two high level sentences summarizing some of the things you can do. No specific instructions, illustrations or even a suggestion to get a book on Tunisian crochet. If you're going to present the question "Can I ABC?", the answer should say a bit more than "yes" and give some useful details on how to do ABC.