* Oceanic Lithosphere: This is the lithosphere under the ocean. It's thinner, typically ranging from 5 to 100 kilometers (3 to 62 miles).

* Continental Lithosphere: This is the lithosphere under the continents. It's much thicker, ranging from 150 to 300 kilometers (93 to 186 miles), and can even reach up to 400 kilometers (249 miles) in some places.

Factors influencing thickness:

* Age: Younger oceanic lithosphere is thinner because it's still cooling and contracting, while older oceanic lithosphere is thicker.

* Density: Continental lithosphere is less dense than oceanic lithosphere, allowing it to "float" higher and thus be thicker.

* Tectonic activity: Areas with active plate boundaries (like subduction zones) can have thinner lithosphere due to the dynamic processes occurring there.

Key Takeaway: The lithosphere isn't a uniform layer. Its thickness varies significantly depending on its location and age, playing a crucial role in understanding tectonic processes and Earth's geological history.