"In Internet slang, a troll (/ˈtroʊl/, /ˈtrɒl/) is a person who sows discord on the Internet by starting arguments or upsetting people, by posting inflammatory, extraneous, or off-topic messages in an online community (such as a forum, chat room, or blog), either accidentally or with the deliberate intent of provoking readers into an emotional response or of otherwise disrupting normal on-topic discussion." - https://en.wikipedia.org/wiki/Troll_%28Internet%29
"Bullying is the use of force, threat, or coercion to abuse, intimidate, or aggressively impose domination over others. The behavior is often repeated and habitual. One essential prerequisite is the perception, by the bully or by others, of an imbalance of social or physical power." - https://en.wikipedia.org/wiki/Bullying
You shouldn't.
"In Internet slang, a troll (/ˈtroʊl/, /ˈtrɒl/) is a person who sows discord on the Internet by starting arguments or upsetting people, by posting inflammatory, extraneous, or off-topic messages in an online community (such as a forum, chat room, or blog), either accidentally or with the deliberate intent of provoking readers into an emotional response or of otherwise disrupting normal on-topic discussion." - https://en.wikipedia.org/wiki/Troll_%28Internet%29
"Bullying is the use of force, threat, or coercion to abuse, intimidate, or aggressively impose domination over others. The behavior is often repeated and habitual. One essential prerequisite is the perception, by the bully or by others, of an imbalance of social or physical power." - https://en.wikipedia.org/wiki/Bullying