A Webcomic is as simple as that, a comic strip on the World Wide Web.
They vary in format from gag-a-day Garfield-style strips, to dramatic, romantic graphic novels, to Japanese-inspired manga-style comics. The most popular webcomics tend to have a
computer game theme, giving an idea of who their key audience are (or, perhaps, where the author is coming from).
The medium as a whole suffers from the same problems as
Fan Fic and therefore
Sturgeons Law; a low barrier to entry means that the entire 90% of crap is visible. While many of the webcomics on free community sites like
Drunk Duck
are considered low quality, there are a number of high-quality comics that have gained popular and critical acclaim, earning their creators a liveable wage from their work.
One thing that's worthy of note, however, is that webcomics work on a very different set of standards than other fiction. Almost all webcomic authors are working pretty much entirely alone as they both draw and script their comics and most do not plan any further along than to the end of their current story (sometimes not even that far). Many of them also try to adhere to a schedule they aren't really capable of, resulting in them rushing to meet their "deadline" and making mistakes that should be avoidable. As a result, it should be noted that even the 10% not subject to
Sturgeons Law will generally not have the same baseline quality as "professional" works because of the lack of editorial input and lack of required lead time. This is not to say that all webcomics suffer from this, though, and even the ones that do can still be interesting.
Growing in popularity in recent years, webcomics use
tropes just like any other media, and thus can be seen cited throughout the wiki. (Ideally anyway. Wink wink, nudge nudge.)