Mac's are better than windows as far as malware and viruses go, but they are not imune to them, and if you get a good virus then you've really got something! But no matter what the system viruses can be a royal pain. Smart viruses are really bad for instance; I had to go looking for a virus manually as none of the anti virus programs would pick it up. When i did find the file and tried to delete it reappeared right before my eyes under a different name stuff like this is a nightmare!