The theory of plate tectonics describes the movement and interaction of large plates that make up the Earth's lithosphere (the rigid outer layer of the Earth) over the more fluid asthenosphere (the partially molten upper mantle). The theory suggests that the Earth's lithosphere is broken up into several large plates that are in constant motion, and that the continents on Earth are part of these plates.
According to the theory of plate tectonics, the continents are not fixed in place, but instead they have moved over geological time scales due to the movement of tectonic plates. The plates move apart at divergent boundaries, where new oceanic crust is formed, and they move towards each other at convergent boundaries, where one plate subducts beneath the other. The movement of these plates has led to the formation of mountain ranges, the creation and destruction of ocean basins, and the distribution of organisms around the globe.
The theory of plate tectonics also explains the occurrence of earthquakes, volcanic eruptions, and the formation of many geological features. It is an essential concept in the study of geology, providing a framework for understanding many of the Earth's geological processes, and has greatly contributed to our understanding of the evolution of the Earth's surface over time.