The name of this site is Anime and Manga Stack Exchange, so questions about anime and manga are fine. But there are also all these things that are sort of connected to anime and manga in some way, and they're usually considered part of the anime fandom. Which of these things can I ask questions about on this site?
If there is a topic related to anime and manga that you don't see on this list, and you'd like to ask a question about it, you can make a meta post or go to chat and find out if the community would be open to taking your question. You can also browse the list of all Stack Exchange sites to find out if there's a site that might be a better fit for your question.
Light NovelsMany anime, including the Haruhi Suzumiya series, Monogatari Series, and Spice and Wolf, are based on light novels.
Visual NovelsOnly questions about the plot of visual novels are on-topic. Questions about the gameplay are on-topic at Arqade. As an example, you can ask the question "Why did Shirou say that people die when they are killed?" on Anime and Manga; however, the question "Which choices do I make to unlock the True ending of Unlimited Blade Works?" is off-topic here, but on-topic at Arqade.
Games based on animeThis includes the One Piece video games, Dragon Ball Z video games, Lucky Star Moe Drill, and any other game based on an anime or manga series. As with visual novels, only plot-based questions are allowed.
Japanese RPGsThis includes most of the games by Nippon Ichi Software and Gust, e.g. the Disgaea series, Phantom Brave, Makai Kingdom, Atelier series. This also includes games like Xenogears, Xenosaga, Final Fantasy, The Tales series, Pokemon. As with other types of game, only plot questions are allowed; gameplay questions should be asked at Arqade.
Other anime-style gamesThis includes Touhou, Kantai Collection, and THE iDOLM@STER. These games include anime-style art, were created in Japan, and are common interests of otaku. They also have anime and manga adaptations, although you needn't confine your questions to those adaptations.
Anime peripheral cross-media franchisesThis torturously-named category includes things like Vocaloid, .hack, and Love Live: they began as cross-media projects, but always had close ties to anime and the anime fandom, and usually ended up with one or more anime or manga adaptations. However, technical questions on the Vocaloid software or gameplay questions on the .hack games would not be allowed; only "plot" questions about the characters and story are allowed. Mascot franchises like Digi Carat and Super Sonico can also be included in this category.
Chinese and Korean Comics and AnimationManhwa and manhua are allowed here without restriction. We don't have a huge base of interest in these topics, so you might be disappointed in the reaction to your questions, but you can certainly ask them.
Original English Language MangaThese are manga-style comics created by Westerners and published in English originally. E.g. Bizenghast, Princess Ai, Van Von Hunter, Megatokyo, Aoi House.
Anime-style Western animationThis includes Avatar: The Last Airbender, Legend of Korra, and RWBY. In the specific case of Last Airbender and Korra, you are strongly encouraged to take your questions to Science Fiction & Fantasy, where there is a much larger interest in these shows. Including these shows in our site has historically been controversial.
ConventionsMake sure to use the conventions tag.
Anime merchandiseFigures, dakimakura covers, jigsaw puzzles, Legos—we've had questions on all of these. Use the merchandise tag. Note that questions asking for product reviews or shopping lists are off-topic.
Memes and other Internet culture memeInternet culture which is not directly about anime is considered off-topic, even if it uses a picture or character from an anime. E.g. What does "I used to be an engineer" mean? was closed as off-topic since the joke has nothing to do with anime.
Resources resourcesThis includes questions about where to find certain series for sale, where to find series translated into a certain language, and apps, websites, or books with certain features.
Japanese Language and Culture in Anime culture japanese-languageGeneral language and culture questions are off-topic. General language questions are on-topic at Japanese Language Stack Exchange. General culture questions are currently off-topic everywhere on the SE network. There is also a History Stack Exchange where you can ask general questions about Japanese history.
Anime TourismSee this answer for a list of acceptable questions in this area.
1Sadly, the Japanese Culture proposal was closed because it didn't make it through commitment in a year. Hence I removed that line in the answer.– Logan MAug 17, 2015 at 0:00
@LoganM Ah, sorry to hear that Japanese culture didn't make it. Thanks for editing that for me.– TorisudaAug 17, 2015 at 1:15