Plate Tectonics: This theory describes the motion of earth's lithosphere. Earth has about 7 or 8 major tectonic plates and many minor plates. When they move, they determine the type of boundary and along these boundaries, earthquakes, volcanic activity, mountain-building and oceanic trench can occur.
Continental Drift: This is the theory that the continents were once together and they split apart across the ocean bed.
Pangaea: This was the name for the super continent that was formed by all of the 7 continents.
Asthenosphere: This is a zone of earth's mantle that is beneath the lithosphere and this is made of several hundred of kilometers of deformable rock.
Lithosphere: This is the outer part of planet earth and it is made of crust and upper mantel, it is about 100 kilometers thick.
Mid-Oceanic ridge: This are the mountain ranges that spread across the ocean floor.
Rift Valleys: This is a valley that develop along a rift
Subduction: This is the process were the edge of one crustal plate is forced below the edge of another.