One of the difficulties that a serious approach to comics faces is that despite the definitional work of a handful of theorists -- most popularly notable among them Scott McCloud -- "comics" remains a fairly ambivalent term.
How we define "comics" will depend firstly on the context and secondly on our theoretical position with regard to art in ontology. Is a work of art defined by its production or its consumption? Is a poem a different medium from a novel, or only a different form? Is television a different medium from film?
If we understand "Comics" as a medium, then there is a difference between “comics”, “comic books” and “comic strips”. Though all three share characteristics in common, the distinction between them is important to note. “Comic strips” are a form consisting of juxtaposed images, published in a newspaper. In this sense, comic strips are defined by their context. Material produced for newspaper publication is a comic strip. Even after this material has been collected and re-published in book form, it is still a comic strip. A book collection of comic strips is not a comic book any more than a series of short stories published in book form is a novel. In contemporary culture, most comic strips are necessarily short and self-contained, since there can be no assurance of a reader having access to the rest of the story. Comic strips are usually humorous (or constitute an attempt at humour), but this is not necessary, and within the form of “comic strips” exist the genres of adventure strips, gag strips, soap opera strips, superhero strips, etc.
“Comic books” are produced and published in book or magazine form, independently of newspapers. Although by far the majority of comic books historically have been superhero comics, there are of course no inherent restrictions in terms of content or subject matter. Like comic strips, many comic books are published as periodicals, with serial stories. There is, however, no inherent limit on space, and longer “graphic novels”—or, in the words of Art Spiegelman, creator of Maus, “comic books that need bookmarks”(quoted in Versaci 1)—are gaining popularity.
“Comics”, as defined by comics theorist Scott McCloud are “juxtaposed pictorial and other images in deliberate sequence” (McCloud 9). McCloud argues that the term “comics” refers to “the artform—the medium ... [which is] a vessel which can hold any number of ideas and images” (6), and he wishes to define that medium as broadly as possible, “while not being so broad as to include anything which is clearly not comics” (4). He points out that Will Eisner's older definition of “sequential art” applies equally to animation, and even to film, but that those images are not spatially juxtaposed—that “space does for comics what time does for film” (7). McCloud's clunky “pictorial and other” is intended to acknowledge that “letters are static images ... [but] when they are arranged in a deliberate sequence, placed next to each other, we call them words.” (8) McCloud also differentiates between comics and cartoons. For McCloud, although “there is a long-standing relationship between comics and cartoons .. they are not the same thing! One is an approach to picture making—a style, if you like-while the other is a medium which often employs that approach” (McCloud 21). As McCloud, and those influenced by him, uses the term, “comics” is a a plural noun without a singular—like “pants”.
McCloud's definition is helpful, but it is unclear if or why, by his definition children's picture books are not considered comics. Also unclear is what the proportion of text to image (or “pictorial” to “other”) is required for something to be considered “comics”. A text book with illuminating figures or diagrams, in which the diagrams are essential to the understanding of the text, might be considered “comics” by McCloud's definition, so long as the diagrams are juxtaposed in deliberate sequence—as they often are. Finally, by McCloud's definition of the term, it is almost absurd to discuss the history of comics. It seems likely that people have been making use of juxtaposed pictorial and other images in deliberate sequence for as long as people have been attempting to communicate with one another. Certainly they have been doing so for all of recorded history. Comics pre-date writing, at least by McCloud's definition of comics. For McCloud, this is part of the virtue of the definition. But comics exist as a medium defined historically and culturally, and expanding the definition too broadly makes historical-cultural perspectives on the formation of comics as a medium seem deceptively unimportant.
While theoretical definitions have their place, and though it is helpful include theoretical definitions of “comics” here in order that the historical, pragmatic and functional definitions may have a context and may not be assumed to be exhaustive, those functional definitions are eventually necessary. The most valuable of functional definitions may be the traditional definition, since it allows us to join a dialogue with the past on its own terms. Traditionally, then, the first “comic” has been considered Outcault's Yellow Kid, in 1896 (Robinson 12). And though this is usually granted to have been the first comic strip, it is also traditionally accepted that comics did not begin to come into their own until the advent of Superman, superhero comics, and comic books.
McCloud, Scott. Understanding Comics: The Invisible Art
Robinson, Jerry. The Comics: An Illustrated History of Comic Strip Art
Versaci, Rocco. This Book Contains Graphic Language: Comics As Literature