The word "umbrella" comes from the Latin word umbra, meaning "shadow." Market umbrellas are so named because they provide shade from the sun, just like a regular umbrella. These umbrellas are usually made of a sturdy fabric such as canvas or polyester, and have a metal frame that can be opened and closed. Market umbrellas are often used in outdoor cafes and restaurants, as well as at outdoor markets. Some market umbrellas even have lights built into them, so you can use them at night!