It might be obvious that Windows XP improved dramatically during its development, but I won't focus on that here, as it's covered extensively in my Road to Gold article. Instead, let's take a look at what's new in Windows XP, and why it's a must-have upgrade for all Windows users.

Why Windows XP Is Important
Each Windows release has a theme, a reason for it to exist. Windows 95, of course, moved the DOS/Windows world to the 32-bit space, and brought with it a major change to the Windows user interface. Not coincidentally, Windows NT 4.0 was about moving the Windows 95 user interface to the NT world. Windows 98 was a small release designed to add bug fixes and Internet integration, along with new device support. Windows 98 SE, of course, was an even smaller upgrade with the same mission as its predecessor: Add new Internet features, improve stability, and support new hardware. Windows 2000, an NT product, brought a new level of sophistication and compatibility to the business world. And Windows Me--the final 9x product--added stability and digital media features to Microsoft's new consumer line.

With Windows XP, the theme is experiences. XP is designed to enable a new generation of end-to-end experiences for the user, experiences that make the PC easier to use, while being more fun and productive to boot. The term experiences, of course, brings with it the unwanted mark of marketing, but this time, the reality is as good as the promise. You can experience digital photography, digital video, digital music, the Internet, mobile computing, the connected home, real-time communications, and a variety of other experiences using just Windows XP.

Windows XP is also about choice. Contrary to reports that Windows XP was exclusionary, this OS makes it easier for users to decide which applications will work with which tasks. For example, you could use AOL and Netscape for Web and email, and then use Kodak's digital camera software to acquire digital photos, if you wanted. So you don't have to use what Microsoft provides. But for the vast majority of users, what Microsoft does provide in the box is not only sufficient, but actually quite good. That's because the company really thought through each experience end-to-end: What happens when the user plugs in a digital camera? Or a camcorder? It's all in there, and it's about what real users want to do with their computers.

And finally, Windows XP is important because it signals the end of the old DOS/Windows product line. Windows XP is based on a new version of the NT/2000 kernel, dubbed the Windows Engine, which brings the reliability of Microsoft's industrial strength business platform to home users for the first time. That it does so without sacrificing application and hardware compatibility is really the most impressive thing about this release. Microsoft has finally come through on its promise to integrate its consumer and business OS products, and the result is far better than I would have anticipated just a year ago.

Windows XP Versions: Home, Professional and 64-bit
Speaking of consumers and business users, Microsoft is releasing three editions of Windows XP: Home Edition, Professional, and 64-bit Edition, the latter of which will run only on new workstations based on Intel's 64-bit Itanium processor. We won't deal with the 64-bit Edition here specifically, but you can learn about the differences between it and the 32-bit versions in my showcase, Windows XP 64-bit Edition & Windows Advanced Server LE Revealed.

Windows XP Home Edition and Professional are essentially the same 32-bit operating system. Both feature the same kernel and basic capabilities, and unless otherwise noted, everything in this review applies to both versions. The Home Edition, as you might expect, is targeted at home users, or the majority of people who were previously using Windows 98 and Windows Me. Professional is targeted at business users and power users, so it offers business-oriented features and some additional capabilities that would be expected by the more technical people. For a complete rundown of the differences, please refer to my showcase, Windows XP Home Edition vs. Professional Edition. But remember one key fact: Professional is a true superset of Home Edition, so if it's in Home Edition, it's in Pro as well.

Upgrading and Installing
Microsoft is permitting upgrades from Windows 98, 98 SE, Me, NT 4.0, and 2000 to Windows XP (see my showcase, What to Expect from Windows XP, for details on which Editions support upgrades from which previous versions of Windows). What this means is that Windows 95, Windows 3.x, and Windows NT 3.5 do not qualify for upgrades. On a related note, evaluation versions of any Windows OS, including Windows XP, do not qualify for upgrades either. This all makes sense: Computers running Windows 95 or older wouldn't be capable of taking advantage of Windows XP anyway.

Most Windows users acquire their OS along with a new PC purchase. For these people, setting up XP will be a painless affair: The first time you turn on the system, you will be presented with a modified Out of Box Experience (OOBE) sequence called Windows Welcome (Figure), with which you can set up the system for multiple users, Internet access, and the like. Users of new PCs will also be free from Windows Product Activation (WPA), a controversial technology that Microsoft uses to enforce its licensing policies. With WPA, each copy of Windows can only be used with a single PC, but on new PCs,