Hats originally made of wool (although nowadays they are usually made of synthetic fibers) intended to provide warmth in cold weather. Typically, knitted caps have simple, tapered structures, but there are many variants. Historically, wool knitted hats were an extremely common form of headwear for seamen, fishermen, hunters, and others who spent their working days outdoors from the 18th century onwards, and are still commonly used for this purpose in the northern parts of North America, Europe, Asia and other cold regions of the world.
