Concepts inUbi-learning integrates indoor and outdoor experiences
Terrain, or land relief, is the vertical and horizontal dimension of land surface. When relief is described underwater, the term bathymetry is used. In America, topography has recently become an additional synonym, though in many parts of the world it retains its original more general meaning of description of place. Terrain is used as a general term in physical geography, referring to the lie of the land.
more from Wikipedia