It’s impossible to list all the different genres in manga, although some good all-around lists can be found in books like Manga, the Complete Guide (2007), by Thompson, Jason. I’m going to talk about the 4 major market-driven genres, as well as a few genres that I personally love. Note that the names I use for the genres (aside from the 4 mahor ones below) are completely arbitrary.

You will notice that the 4 major genres of contemporary manga are divided by gender, rather than content, per se. (As opposed to graphic novels and comics in the U.S., which are divided into genres like “fantasy,” “memoir,” “science-fiction,” “mystery,” “super-hero,” etc. These genres do exist in Japan, but they don’t dominate the market the way the four genres described below do.)

Shoujo is a genre of manga with some or all of the following:

• a pubescent or adolescent girl protagonist, whose goal is to get with the (pretty) male love interest 
• heterosexual romance
• heterosexual tensions including a.) unrequited love b.) jealous female or male rivals c.) pheromone-drenched young male eye-candies in multiples of 2 or 4, or d.) all of the above
• high school or middle school uniform with slouchy socks (if set in the late 90s, early 2000s)
• elaborate, melodramatic eyes
• fireworks, beach scenes, girls in yukata, and other summer fare
• the conspicuous absence of homework

Of course, I am dating myself. Before the 80s, you would have seen a lot more European white girls with some aquarium-sized glistening eyeballs in the shoujo genre but shoujo readers and writers are becoming more and more Japan-centric.

The word “shoujo” literally means “girl” in Japanese.

Shounen (Shonen) is the generic counterpart of shoujo, aimed at young men. “Shonen” means “boy” in Japanese.

Anime Insider (magazine) had a really funny and accurate breakdown of what makes a title “shonen.” I will post it as soon as I get my hands on it again.

Josei is a genre that is dedicated to the exploration of women’s issues. It usually features either an adult woman or features issues of concern to adult women in Japan.

Seinen – a genre catering to adult male readership.

A few of my fave genres:

Sports Training – this is a sub-genre of shonen and sometimes seinen, in which a young scrawny boy usually starts out the series getting picked on and bullied at school and starts training to become the best (fill in the blank) in Japan. Excellent examples include Hajime no Ippo… 

Magical Girl – This is actually a real genre. TBA

Alternate Japan – Mushishi is a prime example. In this genre, Japan is not the contemporary Japan that exists now but a totally different place where people speak Japanese but have to deal with other things, like – in the case of Mushishi – crazy plant-like life-froms that do mysterious things.

National Revolution - BASARA is the best of these. This is a genre that often falls into the shonen category but BASARA incorporates the fighting and violence of shonen with the glistening eyes and beautiful men of shoujo. Throw in a lot of Japanese geography, military tactics, and a cast of interesting characters that you meet along the way, and you have BASARA.