Mac OS X has a spectacular reputation for stability and security. At this writing, not a single Mac OS X virus has emerged—a spectacular feature that makes Windows look like a waste of time. There's no Windows-esque plague of spyware, either (downloaded programs that do something sneaky behind your back). In fact, there isn't any Mac spyware.
The usual rap is, "Well, that's because Windows is a much bigger target. What virus writer is going to waste his time on a computer with eight percent market share?"
That may be part of the reason Mac OS X is virus-free. But Mac OS X has also been built more intelligently from the ground up. Listed below are a few of the many drafty corners of a typical operating system that Apple has solidly plugged:
The original Windows XP came with five of its ports open. Mac OS X has always come from the factory with all of them shut and locked.
Ports are channels that remote computers use to connect to services on your computer: one for instant messaging, one for Windows XP's remote-control feature, and so on. It's fine to have them open if you're expecting visitors. But if you've got an open port that exposes the soft underbelly of your computer without your knowledge, you're in for a world of hurt. Open ports are precisely what permitted viruses like Blaster to infiltrate millions of PCs. Microsoft didn't close those ports until the Windows XP Service Pack 2.
Whenever a program tried to install itself in the original Windows ...