I got this book when I decided to get serious about computer graphics. It contains examples in both GLSL & HLSL, so you get to see a bit of the syntax of both languages. The book gives a quick overview of many techniques and provides sample code for most of them. Major minus is the very sparing use of theory, which leaves the reader to figure out many details around the implementations on his own. Generally useful to get some superficial knowledge about certain effects & phenomena, but definitely not enough for a real introduction to graphics programming.