This book will focus primarily on the Mac OS X Operating System (10.5 and later). While it's possible to develop applications with PHP and CouchDB on any operating system, I will be restricting most of my discussions to Mac OS X for simplicity and brevity. If you're using a Mac, you can skip ahead to the next section, titled Setting up your web development environment on Mac OS X.
If you're running Windows or Linux, don't worry! I'll give you some setup tips to get you started, and then you can take it from there. Again, it's worth noting that the command line statements that I use in this book are meant for use on a Mac OS. With that in mind, things such as navigating to your working directory, the location of files, and many more may not work as described.