Final answer:
The Earth's crust, a thin layer made of rock, forms the planet's outer surface, while the lithosphere includes both the crust and the upper mantle. Under these lies a silicate mantle and a core with a solid inner part and liquid outer layer. Seismic studies provide indirect evidence about these internal structures.
Step-by-step explanation:
The Earth's outer layer underneath the water and soil is known as the Earth's crust. This layer is composed of rock and is relatively thin compared to the overall size of the planet. There are two types of crust: oceanic and continental, each with distinctive physical and chemical properties. The crust is part of what is referred to as the lithosphere, which also includes the uppermost part of the mantle. Beneath the crust is the mantle, composed primarily of silicate minerals, and beyond that lies the core, which contains an outer liquid layer and an inner solid layer made mostly of iron. We understand the structure of these layers through the study of seismic waves, which give us indirect evidence about Earth's interior.