12. Textures   

Texture Mapping is currently the most effective method of simulating real-world object detail in computer-generated images. Texture maps can be created by synthesis or by digitizing. Synthesis techniques were originally applied only to surface modelling but have now been extended to model 3 dimensional texturing, where they are far more appropriate than the digitizing method.

Progressive Realism Demonstration - the Cow
Texture Synthesis
Displaying Textures on the Screen
Tilable vs Non-Tilable Textures
Applications of Textures
Glossary of Texturing Terminology
Examples of Texture Synthesis.

Textures are very important in increasing the visual realism of an image.