Sometimes trolling is joking, and vice-versa.
Joking means to tease people to have a good laugh for everybody, even if nobody laughed at all or infact, reacted negatively towards it.
Trolling means to tease people to have a good laugh towards themselves or for other douchebags while their richards goes hard behind the computer screen (aka ruining the fun for other people for the troll(s)' own entertainment.)
It's one of the reasons why I react to people like MinnesotaBurns so negatively nowadays. Sure, millions of people who watched his channel laughed at some point, but it's destroying the victim in the process, even if that person deserves it or not.