The outermost layer — solid rock, 5 to 70 km thick depending on location. Everything you've ever seen or touched sits on this thin shell.
~2,900 km of hot, slowly flowing rock. It moves only centimeters per year, but that slow churn drives plate tectonics and volcanoes above.
A ~2,300 km shell of molten iron and nickel. Its swirling motion generates Earth's magnetic field, which shields us from solar radiation.
A solid iron ball, ~1,220 km in radius, at roughly 5,400°C — nearly as hot as the sun's surface, kept solid by immense pressure.