There are a lot of different types of comics, and it should be made clear how manga is defined here. What should be the criteria for something to be manga and, as such, on topic?
Most sites dedicated to manga also include manhwa and manhua. Take for example the cases of:
I think that a looser definition of what is acceptable on this site is warranted based on what is broadly accepted by the western manga community. In that sense, and IMHO, both manhua and manhwa are. There's also the question of size. I don't think that manhua/manhwa oeuvre is really all that broad for the number of questions to be significant.
According to Wikipedia,
Manga (漫画) are comics created in Japan, or by Japanese creators in the Japanese language, conforming to a style developed in Japan in the late 19th century.
I think the definition of manga should focus on mainly the origin, like with anime. While manhua, manhwa, la nouvelle manga, and other forms are inspired by manga, they aren't manga by the American and European definition, and the line must be drawn somewhere. This will also create consistency between the anime and manga definitions.
How anime is defined is answered in How is anime defined?, and most of the answers involve the origin being the primary criteria.
I think we should define "manga" as comics fit one or more of the following:
- Comics created to target the Japanese as the primary audience
- Comics (originally) created/published in Japan (including self-published works), this includes comics adapted from non-Japanese source material (E.g., Batman: Child of Dreams)
- Comics serialized by a reputable publisher, E.g. Kondansha
- Comics that have received an nationally (Japan) or international award (for non-serialized comics), or by a legitimate and reputable panel of judges. E.g., International Manga Award
The line gets a bit hazy when we a dealing with self-published works (including doujinshi) by non-Japanese authors outside Japan, typically these works are NOT considered manga, despite similiar styles and themes. But there are exceptions to these Original English Language manga.
Such cases do not seem to be a frequent occurrence, so we can deal with them on a case by case bases.