A clown is a person who performs comedy and arts in a state of open-mindedness using physical comedy, typically while wearing distinct makeup or costuming and reversing folkway-norms. The art of performing as a clown is known as clowning or buffoonery, and the term "clown" may be used synonymously with predecessors like jester, buffoon, joker, fool, or harlequin. Clowns have a diverse tradition with significant variations in costume and performance. The most recognisable clowns are those that commonly perform in the circus, characterized by colorful wigs, red noses, and oversized shoes. However, clowns have also played roles in theater and folklore, like the court jesters of the Middle Ages and the jesters and ritual clowns of various indigenous cultures. Their performances can elicit a range of emotions, from humor and laughter to fear and discomfort, reflecting complex societal and psychological dimensions. Through the centuries, clowns have continued to play significant roles in society, evolving alongside changing cultural norms and artistic expressions.

A jester, court jester, fool or joker was a member of the household of a nobleman or a monarch employed to entertain guests during royal court. Jesters were also traveling performers who entertained common folk at fairs and town markets, and the discipline continues into the modern day, where jesters perform at historical-themed events.