Green beret
U.S. Special Forces wear the green beret as a distinction of excellence and uniqueness within the Army.
Special Forces (United States Army)
In countries other than the U.S., the term "special forces" or "special operations forces" (SOF) is often used generically to refer to any units with elite training and special mission sets. In the U.S. military, "Special Forces" is a proper (capitalized) noun referring exclusively to U.S. Army Special Forces (a.k.a. "The Green Berets"). The media and popular culture frequently misapply the term to Navy SEALs and other members of the U.S. Special Operations Forces.