The Earth is layered.  The outermost layer is the crust, which is a thin layer.  Oceanic crust is ~30 km thick and continental crust ~70 km thick.  Beneath the crust is the mantle, which can be further subdivided, extending down to about 2880 km depth.  At that depth we encounter the liquid outer core, which has a radius that is 55% of the Earth's total radius.  The inner core (solid) is then at 5155 km depth.