A comb is a tool used to care for hair or other fibers. It has small pieces sticking out of a main frame; these are called "teeth." A comb is usually flat.
Humans have been using combs as a tool for a long time, at least for 5,000 years. Combs are used by humans to separate tangled hairs, to keep their hair clean and to style their hair. They are also used as a decoration for hair.