Q: is that many people use internet security for their mac

If you mean Anti Virus Software... See Here... Antivirus Discussion

Reed Here  >  http://www.reedcorner.net/mmg/

Mac OS X tends to look after itself... To keep your Mac Happy... See Here...

http://support.apple.com/kb/HT1147

http://www.thexlab.com/faqs/maintainingmacosx.html

Mac OS X: About background maintenance tasks

I have read in many other threads that using Internet security software actually creates problems with the computer in many cases. AnaMusic gave you good discussions to read. If you are at home behind a router you probably don't need to turn on the firewall either.

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