Apache 2 Pocket Reference
There's no question that Apache powers the World Wide Wide. It runs over half of the world's web sites. If you work in the web industry then there's every chance that you'll have to deal with Apache at some point. Like many people, I don't consider myself a webmaster, but I run several web sites using Apache so I need to know how to get the most out of it.
Over the years, I have bought several books about Apache. They tend to get read once and then left to gather dust on the bookshelf. I never really need an in-depth knowledge of Apache, but I often need to know all about the one feature that I need to solve my current problem. Usually this involves a lot of Googling, but now I think I'll have this book on my desk and it will save me a lot of time.
This book does exactly what the title implies. It is a complete (but concise) reference to Apace. In particular, most of the book is taken up with descriptions of Apache's myriad configuration options. This material all uses a standard layout which makes it easy to find and understand exactly the information that you need. One particularly nice touch is a key at the top of each entry telling you which contexts a configuration option can be used in. Never again will I have an excuse for putting an option in a .htaccess file when it only works in a direcotry context.
There is a lot of information packed into this small book. No space is wasted cramming the data in. But it's not too dense to be unusable. The information is always clear and easy to follow.
If you're a part-time Apache webmaster like me, then I think you'll find this book very useful.