Think of Earth as a huge ball. Its center is called the core. Wrapped around the core is the mantle. These rock layers are super hot. They’re so hot, the rock is in a liquid state.
The top layer of Earth is called the crust. Unlike a ball, the planet’s crust is not a smooth, unbroken surface. Instead, it is made up of many huge slabs, called tectonic plates. These plates fit together like a big jigsaw puzzle, but they are always moving—a few inches every year. As the plates move, mountains form.
