The surface of planet Earth is modified by various internal or endogenous processes. These processes are caused by currents that occur inside the Earth with the help of thermal or heat energy.

Currents occur in the planet's mantle. They consist of the slow movement of molten rock. These currents make the tectonic plates above the Earth's mantle move in different directions.

Endogenous processes include the movement of tectonic plates (plate tectonics), mountain orogeny, earthquakes and volcanic activity​.