1. Crust: This is the outermost and thinnest layer, made up of solid rock. It's what we live on and ranges in thickness from about 3-5 miles under the oceans (oceanic crust) to 25 miles under the continents (continental crust).
2. Mantle: This is the thickest layer, extending from the crust down to about 1800 miles. It's mostly solid but behaves like a very viscous fluid over long periods, allowing the plates of the crust to move.
3. Outer Core: This layer is about 1400 miles thick and is made up of liquid iron and nickel. Its movement generates Earth's magnetic field.
4. Inner Core: This is the Earth's center, about 750 miles thick. It's made of solid iron and nickel, despite the intense heat, because of the immense pressure.
Let me know if you'd like more details about any of these layers!
