When you load a PC, one of the things Windows does is check for an installed antivirus program. If it doesn’t find one installed (that it recognizes), it will hound you until you either install one or find the setting to turn that “nag” message off (which takes some searching). Mac’s OS X gives no such warning. I’m not sure if it’s because they feel viruses aren’t as prevalent or because there’s something built in to OS X.
Antivirus programs can slow a system down. Sometimes they slow it down a lot. Today I was running a program called CCleaner on my HP laptop to get rid of unnecessary temporary files and the scan was taking an unusually long time. Now I hardly ever run it (which is why it was able to find a huge amount of files to delete) but I still felt it was taking too long.
I opened the Resource Monitor and watched the Disk tab. The number one entry under Disk Activity was Avast!, the antivirus program I run on the program. When I temporarily disabled it, CCleaner was able to finish in less than 5 seconds. I haven’t known Avast! to slow down a system to any noticeable degree which is why I picked it but it seems more recent versions may be resource hogs. Either that or there’s something else going on in my system to slow things down. I hope Microsoft Security Essentials on the Boot Camp installation on the Mac does better.
As far as OS X, I can install Sophos, one of the more popular antivirus software on the Mac, but I’m afraid of “lagging” my system. I’m not sure what to do. The Mac didn’t turn the firewall on by default either which is something else Windows will nag you about. The security issues on the Mac seem to be on a different level than in Windows.