Three basic methods for providing surface detail:

1. Texture Map -- Easiest to do, just wrap a picture around a solid. Useful in video games such as Quake.
2. Bump Map -- Slightly more realistic because surface normals are adjusted to provide details, but still fails to modify the geometry so edges and shadows are not realistic.
3. Displacement Map --Best, but computationally expensive because it actually modifies the surface. It also allows you to show evolving surface details.

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