An Oni mask is a type of Noh mask, which is used for depicting characters in Japanese plays. As a part of Japanese culture, the actors and actresses tend to put on masks rather than make-up in order to act out a character. An Oni mask is one of many types of acting masks and is used to depict a character such as a demon or evil spirit.
According to legend, the Noh masks showed up around the Muromachi period (1392-1573). During this time, masks started to lose their meaning as a religious symbol. Noh masks were introduced to the stage as a way of covering the true identity of an actor or actress and displaying the traits of the character in the play. Oni masks are special types of Noh masks that portray beings from other dimensions. Along with Oni masks, there are several other types of masks which are used for different purposes. Men, women, youth and children all have their own type of mask. There is even a type of mask intended for displaying a character that is a ghost. These masks have played a major part in the formation of Japanese culture and are still handmade by select craftsman.