First of all, make sure, you have at least ZBrush version 4.0 installed on your computer.
Note
ZBrush is very fast, but still requires a computer with a bit of horsepower. It takes full advantage of multiple cores in your computer or more RAM-Memory, the more the better. Still, a dual core processor with 1 or better 2 GB of RAM will probably be sufficient to work you through this book. If this is all Greek to you, but your computer isn't age-old, it will probably work out well, too.
Another important point to mention are pen tablets. They usually consist of a tablet and a pen, imitating real drawing on your computer. You can still work in ZBrush just with your mouse, but it is highly recommended to use a pen tablet. They are affordable, depending on the working size you choose. Using ZBrush with a pen tablet not only saves you a lot of time, but is also more fun, because it feels very intuitive and natural.
If you ever tried to paint with a mouse, you know that it's a lot faster with a pencil.
Note
If you think of buying a pen tablet www.wacom.com is a very well-known manufacturer.
This book assumes you're working with ZBrush on Windows. So if you're on a Mac, remember that the Control Key (Ctrl) we'll refer to is the Command Key (Cmd) on your keyboard instead.