“Jaggies” is what happens when you see the edges and corners of the pixels in an image. Imagine having a staircase outline instead of smooth curves around your favorite graphic. And it happens for a variety of reasons. The first and most likely culprit is a low-resolution display. X number of pixels are required to render graphics properly but, a low-res display only has Y to work with. Usually, turning on the anti-aliasing graphic option can help smooth those jagged edges.