Good news: the software that lets your computers hop onto a network is already part of your operating system! You don't need any other complicated software, just maybe a little program called a driver, which is a piece of code that comes with your networking hardware and lets it talk to your computer's operating system.
As far as networks are concerned, all operating systems are created equal. Your network can play host to computers running just about any operating system out there—Windows, Macintosh, Linux, DOS, you name it. But like the pigs in Animal Farm, some operating systems are more equal than others.
Sleek and modern, Windows XP and Mac OS X are particularly good for home networkers, because they're both designed to run multiple accounts and they're compatible with all WiFi equipment. (The term "accounts" here has nothing to do with banking; computer systems like Windows XP and Mac OS X allow each person using the machine to create his own user account with a separate name, password, settings, and files, for both security and aesthetic reasons. Chapters 5 and 6 tell you everything you need to know about accounts.) If your computers are running older versions of Windows or the Mac OS, you can still, of course, join the network party, but you'll have a little more setup work to do. Throughout this book, you'll find specific tips and instructions relevant to all flavors of Windows and the Mac OS.
If you're an all-Microsoft house (using Windows XP, Windows 98, Windows ME, or Windows 2000), you'll find Windows specifics in Chapter 5. Mac mavens will be interested in Chapter 6. And if you've got computers running a mix of Windows and Mac OS X, Chapter 7 walks you through this sort of cross-platform setup.
But before you dash off to Computer Cathedral to buy your network's goods, you first need to decide whether you need a network that's wired, wireless, or both. That's what the rest of this chapter will help you figure out.