1. Crude prototypes of the T-shirt were introduced as an undergarment during World War I, when they were worn by European soldiers during the hot summers. They were the envy of American troops forced to wear wool uniforms.

2. 91% of Americans admit to having a "favorite T-shirt." 34% of those say white is the color of their favorite T-shirt, with almost twice as many votes received as the second most popular color, blue.

3. The origin of the name "T-Shirt" is unclear. Many consider the shape of the shirt as a "T", while it could also refer to the army's use of these pieces as "training shirts". It is also a possibility that the name "tee" comes from the word amputee, an allusion to the arm's shortened length.

4. In December of 2007, Aaron Waltke, 22, a recent graduate of Indiana University in Bloomington set the Guinness Book World Record for most T-shirts worn by a man at one time: 160. Check out the video of the event.