The tricorne or tricorn is a style of hat that was popular during the 18th century, falling out of style by 1800, though actually not called a "tricorne" until the mid-19th century. During the 18th century, hats of this general style were referred to as "cocked hats". At the peak of its popularity, the tricorne varied greatly in style and size, and was worn not only by the aristocracy, but also as common civilian dress, and as part of military and naval uniforms. Typically made from animal fiber, the more expensive being of beaver-hair felt and the less expensive of wool felt, the hat's most distinguishing characteristic was that three sides of the brim were turned up (cocked) and either pinned, laced, or buttoned in place to form a triangle around the crown. The style served two purposes: