Misinformation Troll: this is someone who doesn't really have a clue what they're talking about, however they feel that their input (no matter how wrong) should be provided. This often causes issues with other members who have to correct him (or her) and degrade into conflict.
Off-topic Troll: someone who cannot remain on topic, even when they've gotten either polite suggestions to do so (from staff), or outright warnings to remain on topic. This can either be intentional, or not depending on the troll.
Familiar Troll: someone who uses their familiarity with the site to do what they wish, expecting leniency from the staff. They use trolling methods covered by the other definitions in this post (generally all of them).
Conflict Troll: someone who either baits people, or outright starts a confrontation.
Image Troll: someone who posts images (generally memes) in place of an actual post. Can often be a spam troll.
Spam Troll: someone who spams.
Passive Troll: someone who trolls in a way that often wouldn't be considered trolling, until you take a look at their posting history.
Fed-up Troll: someone who trolls because they are fedup with someone else, more often or not another troll.
Fyi, all forum administrators are trolls in some way or another.