I had always thought that the word trolling had its origins in the sense of ugly dwarf or giant dates to 1610 and comes from the Old Norse word troll meaning giant or demon. But while researching this pot I came across an alternative explanation on the How Stuff Works website:
While the word troll might conjure up images of billy goats and hobbits in your mind, the Internet variety doesn’t really owe its name to the monsters of fairy tales and fantasy. Originally, the Web version of a troll alluded to a fishing technique. In fishing, to troll is to pull a fishing line behind a moving boat in hopes of coaxing a fish to take the bait. Web trolling is very similar — trolls try to lure unsuspecting victims into responding to pointless or rude questions or statements. The goal for the Web troll is to get the victim riled up as a joke. But usually the troll is the only one laughing.