The tectonic plates of the world were mapped in the second half of the 20th century.

Tectonic plates on a different map projection

Global earthquake epicenters, 1963–1998

Global tectonic plate movement

Plate tectonics is a theory of geology. It explains movement of the Earth's lithosphere. The lithosphere is the Earth's crust and the upper part of the mantle. The lithosphere is divided into plates, some of which are very large and can be entire continents.

Heat from the mantle is the source of energy driving plate tectonics. Exactly how this works is still a matter of debate. This theory includes the idea of continental drift.