Anti-virus, firewall and Internet security software

AVG Anti-virus – free; anti-virus 	 
 Microsoft Security Essentials – Free anti-virus and anti-spyware from Microsoft. Supercedes Windows Defender (see below). Also, Security Essentials definitions 
 	 
 Microsoft Windows Defender – Free anti-spyware from Microsoft. Best designated for Windows XP sp3 machines. Included in Windows Vista and Windows 7, and not compatible with Windows 2000. Also, Windows Defender definitions 
 	 
 Norton Internet Security – non-free; anti-virus, firewall, spam/phishing protection, parental control 	 
 Sophos Anti-Virus – shareware; anti-virus. Full version free to UCLA students, staff, and faculty for all Windows versions & Mac OS versions via BOL’s software area . 	 
 ZoneAlarm – free for non-commercial use; firewall 
 
 For general info on securing your PC/Mac you might want to check out: 
 http://www.scribd.com/doc/48356630/MakeUseOf-com-HackerProof-Your-Guide-to-PC-Security