The document summarizes the layers that make up Earth's interior. It discusses that Earth has a crust, mantle, outer core, and inner core. The crust is divided into continental and oceanic crust, and the Mohorovicic discontinuity separates the crust from the mantle. The mantle is divided into an upper and lower mantle by the Gutenberg discontinuity. The outer core is liquid while the inner core is solid. Earth's magnetic field is generated by convection currents in the liquid outer core.