Terrains are stored in the category of native geometries. Their operation is similar to that of Triangle-Mesh geometries, but is optimized to produce the fastest and most stable behavior.
Terrains are composed of a series of triangles that are generated automatically from an elevation bitmap file and construction properties (size, maximum elevation, etc.). Terrains enable you to model precipitous surfaces and rough areas.
You may configure the simulator to build terrains either using native primitives or from a series of triangles. In this latter case, the terrain is considered as a Triangle-Mesh.