Carpet is a textile floor covering that is distinguished from the more general term "rug" by being fixed to the floor surface and extending wall to wall. The earliest peoples covered the floors of their dwellings with animal skins, grass, or, later, woven reed mats. When people learned how to spin cotton and wool, woven mats of these materials largely replaced earlier coverings. Around 3000 B.C. Egyptians sewed brightly colored pieces of woolen cloth onto linen and placed it on their floors.