I promise to get to the point quickly. First, the history lesson:
Once upon a time, there was RT-11. Its operating system progenitor genes, along with those of Unix, are what have evolved into the DNA of the diverse systems we have to deal with today. RT-11 was a DEC operating system that became CP/M. CP/M became CP/M-86. CP/M-86 was mimed into SB/86, which became IBM DOS, which became MS-DOS, which ran a program called Windows, a GUI environment.
The Windows GUI environment arrived from the philosophies behind SmallTalk, an object-oriented GUI. MacOS came from SmallTalk more quickly, then merged with a Unix-derivative, formed by the University of California at Berkeley, known by its initials as BSD. Along the way, a Unix mime was built called Linux, then added to a soup of utilities (GNU) and UIs (KDE, Gnome, among others).
Now there are operating environments like Google's ChromeOS and Android.... not to mention Symbian, Palm, and a half dozen others. Virtualization breaks the rule that existed from RT-11 to just a few years ago in the microcomputer world: one operating system per machine. That idea that became a rule was a boon for hardware makers and operating systems licensors alike. Now that rule is broken by the advancement of hypervisors and desktop hypervisors.
There are few individuals in IT today that can escape knowing at least three major operating trees, starting with Unix, Windows, and to a lesser extent, MacOS. There are dozens of variants. More than a dozen sit on the machine I'm using to write this-- like ducks in a row. Just click and in a few seconds, I'm in OpenSUSE or Windows Server 2008 R2, or in Android. It's that easy.
Fortunately: most all of them fit on desktop hypervisors, like Oracle/Sun's Virtual Box, VMWare Fusion/Workstation, or Parallels. If you don't mind tinkering, VirtualBox is free, and works with most operating systems/environments. We've reviewed all three, and currently VMWare's Fusion (on Macs) is our favorite, but Parallels may retake the baton soon-- VMware and Parallels are neck-and-neck, with VirtualBox only slightly behind. As far as 'smooth' goes, we fight in the lab about which one is better. And we discover new limitations and odd successes with all three every week.
That's because we have to deal with Linux, MacOS, Windows, SunOS, BSD, and many desktop and server versions of each, on an ongoing basis. This is why the 500GB laptop hard drive was invented-- for virtual machines and OS/E hosting and testing. We know we're not the only ones that do this. We're the only ones crazy to believe that this may never end, and we don't care, and soon, you won't either. Well, perhaps the cost of some licenses or their possible constraints might. In fact, perhaps they already do.
And therefore, the point: if you haven't tried it, get a little ahead of the pack. Start with one of the three aforementioned desktop hypervisors and have a good time. The cool thing is you can blow up an operating system and if you didn't really need it, there's no harm at all-- and you learned something! You may find some better time wasting games. Or perhaps a scripting language with half-a-brain.