Introduction

Without a doubt, Mac OS X is a stunning technical achievement. In fact, many tech reviewers and experts call it the best personal-computer operating system on earth. But be ware its name .

The X is meant to be a Roman numeral, pro nounced "ten." Unfortunately, many people see "Mac OS X" and say "Mac O.S. ex." That's a sure way to get funny looks in public.

Then there's the "Mac OS" part ”what a misnomer! Apple designed Mac OS X to look something like the old Mac system software, and certain features have been written to work like they used to. But all of that is just an elaborate fake-out. Mac OS X is an utterly new creation.

If you've never used a computer before, none of this matters. You have nothing to unlearn. You'll find an extremely simple, beautifully designed desktop waiting for you.

But if you're one of the millions of people who have grown accustomed to Windows or the traditional Mac OS, Mac OS X may come as a bit of a shock . Hundreds of features you thought you knew have been removed, replaced , or relocated . (If you ever find yourself groping for an old, favorite feature, see Appendixes C and D ”the "Where'd it go?" dictionaries for Mac OS 9 and Windows refugees.)

Why did Apple throw out the operating system that made it famous to begin with? Well, through the years , as Apple piled new features onto a software foundation originally poured in 1984, performing nips and tucks to the ancient software to make it resemble something modern, the original foundation was beginning to creak. Programmers (and some users) com plained of the "spaghetti code" that the Mac OS had become.

Apple felt that there wasn't much point in undertaking a dramatic system-software overhaul if they couldn't master every key feature of modern computer technology in the process, especially crash-proofness. Starting from scratch ”and jettisoning the system software we'd come to know over the years ”was the only way to do it.