Currently Being ModeratedMay 9, 2013 5:25 PM (in response to marysister)
OS X; 10.7 & 10.8: http://support.apple.com/kb/ph11273
Currently Being ModeratedMay 9, 2013 5:37 PM (in response to marysister)
If you are doing this because you want to sell it, please be advised that if you updated it to Lion or Mountain Lion (10.7 or 10.8), the license is not transferable and you are required to wipe the drive and reinstall the original OS. If you sell it with one of those OS's, the buyer will never be able to reinstall because the license is tied to your Apple ID forever.