The infinite canvas is the idea that the size of a digital comics page is theoretically infinite, and that online comics are therefore not limited by conventional page sizes. An artist could conceivably display a complete comics story of indefinite length on a single "page". Scott McCloud introduced the concept in his book Reinventing Comics.
Although McCloud asserted that this freedom was one of the most important qualities of the online comics medium, relatively few webcomics have taken advantage of it; most produce work in more traditional formats such as the serialized comic strip and the rectangular page, rarely exceeding two screens in height. The unpopularity of infinite canvas techniques can be attributed to a few factors: a general aversion to excessive scrolling, particularly horizontal scrolling, among online readers; the problem of long load times for large image files; and the difficulty of producing comics with very large dimensions. Keeping comics in traditional page format also eases the writer's transition into publishing their comics in print format, as expressed by at least one writer; and limiting the size of comics makes them more accessible for readers who access the comic not through the regular site but, for example, through RSS readers or the Wii internet browser.
Nevertheless, the core concept of a lack of intrinsic restraint on comic sizes has often been applied. Comics such as El Goonish Shive and Dominic Deegan: Oracle for Hire were easily able to change their standard format from one line to two when their respective cartoonists decided to; likewise, Megatokyo made a smooth transition from traditional four-panel comic strip to full-page graphic novel. Webcomics such as Narbonic and Fans take advantage of the medium on occasion for special effects (e.g. the time-shift effect in "Dave Davenport Has Come Unstuck in Time"), and even sometimes use the "gradualism" effect McCloud describes. Even four-panel comics benefit by not having their comics "squeezed" onto a newspaper page to the point of illegibility, and thus can include more detail. (Part of this is also due to computer screens being much "cleaner" than newsprint.)