The knit cap -- soft, warm and shapeless until it's pulled onto your head and over your ears -- has been around for centuries. It is so ubiquitous that it's a newborn's first fashion accessory. The hat has come to be known as a beanie in the fashion world, but it's been called by many other names. In fact, "beanie" used to mean a different kind of cap entirely.

Whether you call it a beanie, a toboggan, a watch cap, a toque, a skullcap or just a cap might depend on where you live and how old you are. The cap's roots go back to the Monmouth cap in Medieval England, where it was everyday wear for workers. It made its way to the New World with sailors and was adapted by lumberjacks, farmers and anyone else who needed to keep warm. The U.S. Navy issued "watch caps" and olive drab "Jeep caps" that could be worn under helmets. The toboggan name, of course, was adapted by sledders. According to The Word Detective, skateboarders in the 1990s started calling the caps "beanies" -- and the name has stuck.

Another type of cap, round with a brim and often sewn from pie-slice-shaped cutouts of school colors, was also called a beanie. It was required attire for freshmen or others going through college hazing in the first half of the 20th century. Later, a cartoon series, "Beany and Cecil," added a propeller to the cap, creating a sci-fi, geek-chic phenomenon in the 1950s and '60s.