The lithosphere is the outermost layer of the Earth's surface, and it is made up of the crust and the upper rigid mantle. The crust is the thin, solid outermost layer, while the upper rigid mantle is the solid layer beneath the crust. Together, they form the lithosphere, which is responsible for the movement of tectonic plates and the formation of continents and ocean basins. The inner and outer core are not part of the lithosphere, as they are located deeper within the Earth.