Why people Troll

A recent survey found that 60% of people have been harassed online. Most people believe that trolling is done by small, vocal minority of sociopathic people.

Studies has also shown that trolls have personal and biological traits such as sadism and propensity to seek excessive stimulation.

Trolls are ordinary people like you and I
Negative moods and discussion context is what majorly influence trolling.

Trolling also can differ in severity, from swearing to targeted bullying, which necessitates different responses.

It's also important to differentiate the impact of a troll comment from the author's intent: Did the troll mean to hurt others, or was he or she just trying to express a different viewpoint? This can help separate undesirable individuals from those who just need help communicating their ideas.

When online discussions break down, it's not just sociopaths who are to blame. We are also at fault. Many "trolls" are just people like ourselves who are having a bad day. Understanding that we're responsible for both the inspiring and depressing conversations we have online is key to having more productive online discussions.

Edited from livescience