In The Comics (1947), early comic historian Coulton Waugh linked the definition of comics with the newspaper medium itself. Comics could only be comics if they appeared in a paper. Thus, to him, the history of comics must begin in 1896 with Outcault's Yellow Kid. While Waugh tended to overlook kindred art forms, such as political cartoons, children's book illustrations, and serial illustrations, M. Thomas Inge in Comics As Culture (1990) casts a wider net over the subject. Inge's definition of comics tries to account for various characteristics, such as open-ended narrative, recurring characters, timelessness, and dialogue balloons. Inge also notes the similarity between comics and photography, theater, and motion pictures. The Yellow Kid, while possibly not the first true comic, becomes important as one of the early comics to invoke those characteristics.

Perhaps the best definition of comics to date comes from comic book artist Scott McCloud. In his Understanding Comics (1993), McCloud separates content from form and develops an aesthetic of comics applicable to different media. He eventually settles on defining comics as "juxtaposed pictorial and other images in deliberate sequence, intended to convey information and/or produce an aesthetic response in the reader." (p. 9) This allows McCloud to trace the history of comics to Pre-Columbian picture stories of Central America and the Medieval Bayeaux Tapestry. The Yellow Kid becomes a part of that continual stream of comic aesthetics.