Computer viruses and the like have long been far more common on Windows computers than on Apples, simply because those who write them target the bigger market share. But now two Mac worms have surfaced and, reports the Wall Street Journal, they "tripped alarm bells …. because they were part of a very small handful of malicious Mac programs, known in the tech world as malware."
New word to me. By the way, can anyone explain to me the differences between a virus, a worm, and a trojan?
This explains it better than I could. To summarize, a virus is something which infects your computer. A Trojan is a virus which infects another program, and when you launch that program, the virus gets launched as well. A worm is a like a virus, but it can copy itself onto other computers.
Typically a worm is the worst, as it infects other machines, while a virus only hurts one. The terms tend to be used interchangeably though, with virus the generic term for all malicious computer programs.