Final answer:
The crust is the outer layer underneath the surface of the Earth. It is divided into continental and oceanic crust, which have different physical and chemical properties.
Step-by-step explanation:
The outer layer underneath the surface of the Earth is called the crust. The Earth's crust is a thin, brittle outer shell made of rock. It is divided into two types: continental crust, which makes up the landmasses, and oceanic crust, which makes up the ocean floors.
The continental crust is thicker, less dense, and composed mostly of granite, while the oceanic crust is thinner, denser, and made mostly of basalt. These two types of crust have different physical and chemical properties.
Below the crust, there are other layers, such as the mantle, outer core, and inner core, which make up the Earth's interior.