Riemannian geometry

Riemannian geometry is a type of geometry, like the kind you learn in school. The main difference is that in Riemannian geometry, the size of shapes can change depending on where you are. For example, a square drawn on the surface of the Earth would get bigger or smaller as you moved away from the Equator. Like other kinds of geometry, Riemannian geometry helps us understand how things work in different places in the world.