Troll: A supernatural creature of Scandinavian folklore, variously portrayed as a friendly or mischievous dwarf or as a giant, that lives in caves, in the hills, or under bridges.
Powman, as long as you avoid taking up residence in caves, in the hills, or under bridges you should not be mistaken for a troll, ala Lord of the Rings.
OTOH, discussion board trolling refers to trying to elicit a strong, usually negative or angry, reaction by deliberately posting controversial or inflamatory statements. For example, "Hyundai Tuscons suck."

Kidding. I'm a kidder.