Sock and buskin
The sock and buskin are two ancient symbols of comedy and tragedy. In Greek theatre, actors in tragic roles wore a boot called a buskin. The actors with comedic roles only wore a thin soled shoe called a sock.
Melpomene, the muse of tragedy, is often depicted holding the tragic mask and wearing buskins. Thalia, the muse of comedy, is similarly associated with the mask of comedy and comic’s socks. Some people refer to the masks themselves as "Sock and Buskin."
