What is the innermost layer of the Earth called?

The CORE is the innermost layer of the Earth. ASVAB General Science includes earth science. Earth's layers from outside in: CRUST (thin outer layer where we live); MANTLE (thick middle layer of hot, semi-solid rock); CORE (innermost — divided into a liquid OUTER CORE and a solid INNER CORE, composed mostly of iron and nickel, extremely hot). The Earth's core generates the magnetic field. Knowing Earth's layered structure (crust, mantle, core) is commonly tested earth science.