Comedy is a mode of discourse that operates across many different genres, media, and styles. Just as there are comic films, there are comic plays, music, paintings, sculptures, and photographs. Comedy has its own aesthetic that is distinct from, but invariably related to, tragedy. It is as central to the human condition as any other aspect of human life, yet the amount of serious academic study it has received is relatively small. One of the advantages of using semiotics as a methodology for studying comedy is that it is versatile and interdisciplinary enough to explain how comedic meaning is created in a variety of art forms. This dissertation attempts to develop a semiotic theory of comedy by reconciling existing comedic theories with semiotic theory and to explore the nature of comedic meaning as a corruption, reversal, or undermining of conventional semiotic meaning. This theory is used to analyze various artworks to show how a semiotic analysis of the comedy in those works can be used to understand not only how the works produce comedy, but to provide insight into the nature of comedy itself. While this dissertation addresses comedy in a variety of art forms that have typically been under-represented in semiotic scholarship, it also pays specific attention to film, which is ideally suited to an interdisciplinary study of comedy. Comic film is inherently interdisciplinary, often includes verbal or linguistic humor, frequently has a comedic narrative structure, can include comedic music, and is a visual medium that has the most highly-developed forms of visual comedy. It is fertile ground for examining how comedy can function on a variety of levels and in a variety of formats. Because a semiotic approach to comedy has received limited attention in English-language discourse and a semiotic approach to comedy has not been fully integrated as a theoretical approach, this work opens a new avenue of study. It expands not only the field of semiotics, but also provides an alternative method for understanding why and how comedy functions in a variety of art forms, specifically addressing comedy as an aesthetic phenomenon.