What's a winter cap ?
A knit cap, originally of wool (though now often of synthetic fibers), is designed to provide warmth in cold weather. Typically, the knit cap is of simple, tapering constructions, though many variants exist. Historically, the wool knit cap was an extremely common form of headgear for seamen, fishers, hunters and others spending their working day outdoors from the 18th century and forward, and is still commonly used for this purpose in the northern regions of North America, Europe, Asia, and other cold regions of the world. Being found all over the world where climate demands a warm hat, the knit cap can be found under a multitude of local names.
What a Canadian Tuque ?
In Canadian English, knit caps are also known as a tuque (pronounced /tuːk/; also spelled touque or toque), a word closely related to the French word toque, originally referring to a traditional headwear and now used for a type of chef's hat (short for toque blanche, meaning "white hat"). Toque is also commonly used across New England as well, especially among the working class.
The word is also occasionally spelled touque. Although this is not considered a standard spelling by the Canadian Oxford Dictionary, some informal media polls have suggested that it is the preferred spelling by many Canadians.
In some sections of Canada, a tuque with a brim on it, commonly worn by snowboarders, is nicknamed a bruque (a brimmed tuque).
What's a Bobble Hat ?
A bobble hat' or bobble cap or Bob Cap is a knit cap that has a yarn "bobble" or pom-pom on top. It is similar to a watch cap, although that does not have a bobble.
Bobble hats were traditionally considered utilitarian cold-weather wear. In the early 21st century they were considered popular only with geeks and nerds. A surprise rise in popularity, driven initially by the Geek-Chic trend, saw them become a fashionable and with a real fur bobble, luxury designer item.
Source : Knit Cap Wikipedia