Hi Sakshi,

Terrestrial part of Earth is called the Lithosphere. A lithosphere refers to the rigid, outermost shell of a terrestrial planet or natural satellite, which is defined by its rigid mechanical properties. Earth's lithosphere includes the crust and the uppermost mantle, which makes up the rigid and hard outer layer of the Earth. The lithosphere is subdivided into tectonic plates.There are two types of lithosphere, oceanic lithosphere, which is associated with oceanic crust and exists in the ocean basins. The second one is continental lithosphere, which is associated with continental crust or the land area on Earth.

Hope it is helpful.