Although most people think of superheroes when they think of comic books, there are several other genres for collectors to enjoy, including alternative/esoteric, manga, science fiction, fantasy, action/adventure, horror, humor, romance, children's, and adult. Superhero comics are most popular in the United States. They are similar to modern day mythology, with fantastical settings and characters with superhuman powers and abilities. Common examples include Wonder Woman, X-Men, Superman, Spiderman, and Batman.
Alternative/esoteric comic books are often more realistic than those focused on superheros, but they do not necessarily have to be real to life. Readers who want to think a bit more about what they are reading often enjoy them. Some are about fictional events, while others are educational or based on history. They tend to receive more critical recognition and acclaim. Examples include American Splendor, Strangers in Paradise, Ghost World, and Sandman.
Manga comic books are Japanese, but they're usually translated into English in the US. They are very popular, and the manga style is reproduced in countries around the world. Science fiction comics tell futuristic stories that incorporate advanced technology and, usually, travel through space. Many superhero comic books also fall into this category, but they still compose a genre of their own.
Comics in the fantasy genre involve fantasy creatures, swords, sorcery, and mythological figures. Some of the most successful ones are also turned into very successful fantasy novels, like the Conan the Barbarian series. Perhaps the opposite of the fantasy genre, action/adventure, usually involves characters that do not have special powers. Rather, they are everyday people experiencing a conflict. Most of the characters, however, are detectives or police, and the story focuses on their battles against criminals.
Other comic books center on horror, including characters such as zombies, monsters, and vampires. They tend to be gruesome and often include nudity and profanity. Humor comics also generally contain dark themes. They are not strictly funny, and often cross over into many different genres. Similarly, romance comics may also cross over to other genres. In fact, comic books that are strictly about romance are no longer very common. Children’s comic books are also not that common, but those that are are generally whimsical and humorous.
Additionally, there are comics geared strictly towards adults, but many mainstream bookstores do not carry them. Rather, most are downloaded from the Internet.