The United States Army Special Forces —Special Forces or SF — is an elite Special Operations Force of the United States Army trained for unconventional warfare and special operations. The SF was founded in 1952 by Colonel Aaron Bank, and its members are popularly known as the Green Berets, because of the unit's distinctive green beret headgear. Their official motto is De Oppresso Liber (Latin: "To free the opressed"), a reference to one of their primary missions to train and assist foreign indigenous forces.
Special Forces units are tasked with seven specific missions: unconventional warfare, foreign internal defense, special reconnaissance, direct action, combating terrorism, counter-proliferation, and information operations. Other duties include coalition warfare and support, combat search and rescue (CSAR), security assistance, peacekeeping, humanitarian assistance, humanitarian de-mining and counter-drug operations.