In simple terms, Mime Theatre (also called Theatrical Mime) is mime for the stage rather than mime for the street. While Marcel Marceau's popular success spawned imitators on sidewalks, boardwalks, and cafés worldwide, Marceau himself was never a street artist, but always a stage artist. Street Mime is an art in itself and can lay claim to many talented performers, but is generally more improvisational and audience-interactive than Mime Theatre. Mime Theatre is actor-centered performance in which the body is the primary means of expression. It can vary from a single performer to a full cast, and from a bare stage to a production employing all the arts that belong to the theatre – lighting, music, costume, makeup, scenic design.
Many think of mime as a sort of "illegitimate art" whose practitioners bother pedestrians and demonstrate cliché illusions. Mime Theatre is a genre of theatre as old as theatre itself, and can be as profound, poetic, comic, or dramatic as any art of the stage. With its roots in ancient Greece and the Commedia dell'Arte, it has developed in modern times into a highly-skilled actor's art that requires extensive study of its dramatic principles and physical techniques.
Mime Theatre is a complete art in itself, and those who learn it will find it also enhances their work in other performance arts such as traditional theatre, acting for film and television, dance, improv theatre, stand-up comedy, and more. (See some of the people who have studied mime.)