UV mapping is a process of applying textures to an object by hand. With the procedural textures of last chapter, you made a material and changed its properties to create the look of a surface texture you wished to emulate. However, there are limitations to how much a procedural map can do. If, for example, you want your company logo on the side of your model, procedurals aren't going to do; you need the accuracy of manually painting your texture onto the surface. Table 5-1 compares the two techniques.
Table 5.1. Procedural and UV-Mapped Textures Compared
No texture files needed
Very flexible with regard to experimentation and fine-tuning
Paint applied to textures directly in 3D ...