AVG PC SECURITY 2012:

                   

Anti-Virus Guard (AVG) is a family of anti-virus and Internet security software for the Microsoft Windows, Linux, Mac OS X, and FreeBSD computing platforms, developed by AVG Technologies, a publicly traded Czech company formerly known as Grisoft.

Features

AVG features most of the common functions available in modern anti-virus and Internet security programs, including periodic scans, scans of sent and received emails (including adding footers to the emails indicating this), the ability to "repair" some virus-infected files, and a quarantine area: "virus vault/chest" in which infected files are held.
A handy & clear (if somewhat misleading) feature / product comparison table is at Free vs Paid

Resource requirements

AVG usually supports several products and usually the two latest versions of each, as well as the AVG Beta Program. Additionally, each product is available for only certain operating environments ("System Requirements").

Version 2012 of AVG (Basic, Internet Security, ...) released in 2011. AVG also advertises 3rd party services to remove what AVG doesn't/can't.

Version 2011 of 5 AVG products (Free, Business, Home) for AVG & AVG Internet Security, ...) (A fake version has also appeared in this version as a virus. The fake version may take internet explorer to pretend to warn them that a site contains malicious software and redirect people to a secure less sites in the internet. It can block access to task manager and other legitimate software and misleads people into paying the full version of the fake software. It also shuts down the system with Virtumonde. It's mostly recommended to copy and paste the URL so they can avoid an unexpected shutdown. This rogue version cannot be uninstalled normally, they must use any malware removal in order to remove the fake AVG software and it's malware that doesn't normally install with the software.) 

Version 9 of AVG (Free, Internet Security, ...), released before June 2010.