Anti-Aliasing

From IeXwiki

The removing of "Stair Stepping" effect on graphics. A graphic is resampled typically 2 or 4 times (hence 2x and 4x Anti-Aliasing) and different shades of grey are drawn around the image, fooling your eye into thinking it's smoother then it actually is. The downside of Anti-Aliasing, it uses a lot of GPU power, causing considerable frame rate loss.