Graduation Hats or the Oxford Cap is a skull cap with a square board in place of a crown with a tassel attached at the center. As the square board resembled the brickfield workers’ mortarboard, these hats are sometimes also known as a mortarboard.
Graduation hats are worn along with the graduation gown or robe during the university graduation ceremony worldwide. It is believed to be a variant of the Biretta. However, the square hat is at times replaced by a Tudor Bonnet or a Tammie, mostly for women.
The most common color of the Graduation Hats is black, but at times, other colors are also popular that match with the rest of the attire.