Trolling: The art of deliberately, cleverly, and secretly pissing people off, usually via the internet, using dialogue. Trolling does not mean just making rude remarks: Shouting swear words at someone doesn't count as trolling; it's just flaming, and isn't funny. Spam isn't trolling either; it pisses people off, but it's lame.
Signs that your trolling is unsuccesful:
*Your victim identifying you as a troll.
*Identifying yourself as a troll.
*Your efforts being ignored.
*Being counter-trolled (See below