Ski masks are called balaclavas.
Robin Hood is commonly depicted wearing a bycocket.
Napoleon is commonly depicted wearing a bicorne.
Pilgrims are commonly depicted wearing capotains.
Keystone cops wore custodian helmets.
Sherlock Holmes is commonly depicted wearing a deerstalker.
The newsy hat has like 8 names, ranging from apple cap, to baker boy, to gatsby.
That poofy fuzzy Chassidic Jew hat is called a shtreimel (plural is shtreimlech).
Graduates wear mortarboards.
The Smurfs wear Phrygian caps, which the Ancient Romans gave to freed slaves.
Those white safari hats are called pith helmets.
Santa Claus is commonly depicted wearing a stocking cop.
Those fuzzy Russian hats are called ushankas, and they became ubiquitous because the government used to give them to workers for free.
Those red skullcaps worn by Catholic priests are called zucchettos.
The triangular Vietnamese hat is called a nón lá (leaf hat).