Manga: Japanese word for what we in the US call "comic books", but not really.
In Japan, the tradition of graphic novels, comics, what have you, is not only quite old, but cuts across genre and age categories in ways we westerners have a hard time imagining. There are manga that deal with every subject imaginable - there are romance manga, office politics manga, sports manga, and, of couse, science fiction, fantasy, etc.
And all ages read it, and there are manga targeted for all age groups, including some rather perverse adult manga.
From manga, we get Anime, or animation. Again, anime is not a genre (despite what some people think), it is a medium. There are as many different types of anime as there are Hollywood films. We don't get a lot of the more "mainstream" anime here, we mostly get the fantasy, big boobs, giant robots, etc. But this is only part of anime.
In the US, anything that is animated has a 99% chance of being oriented towards kids. Big shock for westerners when they start to see what's available in anime. I would guess a large chunk of anime is targeted at the same teenage crowd that PG-13 movies are here.
Hope this clears things up.
