House Entrance Doormat

A mat is a generic term for a piece fabric or flat material, generally placed on a floor or other flat surface, and serving a range purposes including:
providing a regular or flat surface, such as a mousepad.
protecting that which is beneath the mat, such as a place mat or the matting used in archival framing and preservation documents and paintings.
protecting that which is above the mat, such as a wrestling or gymnastics mat, or an anti-vibration mat.