What is Manga?

Literally "silly words", manga are Japanese graphic novels analogous to the American "comic book". Unlike the comic book, however, nearly all manga are black and white, with perhaps a few color sections added for effect. Whereas "comic books" tend to come out on a monthly basis with one "episode" to a volume, manga tend to contain several "episodes" in each volume, which results in the average manga being roughly two hundred pages long, per volume.
Due to the mode of reading Japanese, manga read right to left, and top to bottom. This is an exact mirror image of the way "comic books" read, but is not hard to adjust to. In much the same way that companies are subtitling or dubbing anime to release to fans in English-speaking countries, several companies are releasing "English" versions of manga with the dialog and text notes translated, but the art intact. This is an enormous boon to fans, but it is sadly the case that these editions can actually go out of print before the Japanese version. To facilitate reading by English-speaking fans, these translated manga are often mirror-imaged so that the flow of the action is left-right rather than right-left.