The Inner Core is a very hot and solid material that changes with pressure. This center is hotter than the surface of the Sun and also spins in the same direction as the Earth, just a little faster!
The Outer Core is a liquid substance made mostly of Iron and Nickel. It is believed this layer is the reason for our Magnetic Field on Earth.
The Mantle is considered a balance between heat and pressure. The rock consisting of this layer is very fluid but also rigid at the same time. This layer helps the drive of plates on the upper layer.
The Lithosphere is a solid layer. This layer carries the Earth's continents and oceans.
The Crust is the thinnest layer and also the layer which contains all life. Some areas are very thick, and other areas are very dense.