Here's a breakdown:

* Erosion: The process of wearing away and transporting rock and soil by natural forces like wind, water, and ice.

* Pediment: A gently sloping, erosional surface at the foot of a mountain or cliff, formed by the erosion of bedrock by sheetwash (a thin, continuous flow of water).

Pediments are typically found in arid and semi-arid regions where rainfall is infrequent but intense, leading to sheetwash erosion. They can be quite extensive and often form the base for alluvial fans, which are cone-shaped deposits of sediment at the bottom of canyons.