This could mark the beginning of the end of old-fashioned single-operating-system PCs. That's what every drab Windows PC is, by the way.
Al Fasoldt's reviews and commentaries, continuously available online since 1983

T e c h n o f i l e
How Parallels Desktop turns a Mac into a Mac-plus-Windows PC

April 22, 2007

By Al Fasoldt
Copyright © 2007, Al Fasoldt
Copyright © 2007, The Post-Standard

   Emulation is the sincerest form of flattery if you're a computer.
   Through emulation, a Mac can pretend to be a Windows PC. A Windows PC can pretend to be a Linux PC. Or a single computer can gird itself for heavy-duty action and pretend to be two or three different computers at the same time, each one running a different operating system simultaneously.
   Mac users have gained the most from emulation over the years. Microsoft's monopoly guarantees that some of the software used in homes and offices will never be available for any computers other than Windows PCs. Through emulation, Mac users have been able to run such Windows-only programs as Microsoft Access and Microsoft Outlook.
   But the word "run" -- as in my previous sentence about Mac users being "able to run" Windows programs via emulation -- is more than a little misleading. "Walk" would be a better word. Emulation requires millions of software translations a second to work well. But even when it works well, it's slow.
   That's why Apple's big switch to Intel computer chips is so important. When Apple computers used their previous kind of chips, running Windows on a Mac meant suffering along with emulation. Things ran so slowly that programs requiring a lot of graphics wouldn't run at all. And games? Forget it.
   But Apple knew it would have a market to itself as soon as it could switch all its Macs to a new kind of Intel central-processing chip. The new chip had two huge advantages: First, it was a PC chip, the same kind that Windows PCs used, and second, it was capable of a new kind of emulation.
   The new kind of emulation is called "virtualization." In a chip that supports virtualization, the computer doesn't have to pretend it's something else. It simply focuses its attention on two or more totally different main tasks -- running the computer's own operating system, for example, while running a completely different operating system at the same time.
   In all current Macs, this means the computer can run Mac OS X, Apple's own operating system, while simultaneously running any version of Microsoft Windows.
   To make use of this capability, you need to add a relatively inexpensive utility program to your Mac. It's called Parallels Desktop, from from www.parallels.com. It costs $79.
   Parallels Desktop has three personalities:
   It can create a virtualized Windows PC inside a Mac OS X window. This is the classic way of running Windows on a Mac.
   It can let you switch from a full-screen Mac OS X system to a full-screen Windows system. Both computer operating systems are running at the same time, even if one of them is hidden away using this method.
   Amazingly, it gives you a simple way of running Windows programs on your Mac desktop alongside Mac OS X programs. In this mode, Windows programs are shorn of their Windows desktop -- they even have OS X Dock icons -- and simply look like drab versions of OS X programs.
   This is the coolest software I've seen in years, and could mark the beginning of the end of old-fashioned single-operating-system PCs. After all, if you can buy one computer and get the ability to run all those modern virus- and spyware-free OS X programs while still being able to launch any of your "mandatory" Microsoft programs, why would you want to choose any other kind of computer?