Learning about various image technologies

Hi-
I just wanted to know if anyone could point me to a good learning page that would show me various tutorials/faqs regarding such things as image rendering geometry, anti-aliasing, file type technical descriptions, etc... etc... I am taking over some code from a former employee, and I really need to get informed the basics, as I've been server side for a long time now! I appreciate any help you can give!
Thanks-
John