What is MSAA

Hi! I just installed NBA 2K9 on my PC. When I tried to tweak the Graphics, I stumbled on the MSAA settings. What does MSAA settings do and how would I know its enough for my PC. Thank you.

Multisampling Anti-Aliasing. - gets rid of the jaggies by rendering at a higher resolution then reducing it to your screen size. So i think the settings will determine how many times higher the game will render as opposed to your screen resolution. Thus, in theory, the higher the smoother your game looks.