It is not uncommon to witness Internet cruelty at the hands of Internet trolls. Internet trolls can be especially harmful, taking advantage of online anonymity and de-individuation. There is certainly a knowledge of psychology necessary to understand those who take part in Internet trolling. There is a threat associated with the troll, in that they can cause significant emotional, and sometimes even physical, harm.
When people become anonymous and lose their identities in a group, they are more likely to take part in activities that can cause emotional harm. The loss of individuality and accountability makes it easy to blend in. Trolls love the protection of anonymity, which allows for misrepresentation and lies. Men can pretend to be women and 14 year olds can pretend to be in their 30s. Trolls also thrive on the fact that conversations are not happening in real-time. This makes a troll feel as if the harm they do isn’t real.
Source: The Internet Troll