Robin Hood is a heroic outlaw in English folklore. A highly skilled archer and swordsman, he is known for "robbing from the rich and giving to the poor," assisted by a group of fellow outlaws known as his "Merry Men." Traditionally in films Robin and his men are depicted wearing Lincoln green clothes. Some accounts give the colour worn by Robin as scarlet or red, which may provide an explanation for the name "Robin" as well as "Will Scarlet".
Robin Hood became a popular folk figure starting in medieval times continuing through modern literature, films, and television. In the earliest sources Robin Hood is a commoner, but he was often later portrayed as an aristocrat wrongfully dispossessed of his lands and made into an outlaw by an unscrupulous sheriff.
Source: Wikipedia, "Robin Hood," available under the CC-BY-SA License.