Definition

In Internet terminology, a troll is someone who intentionally posts
derogatory or otherwise inflammatory messages about sensitive topics
in an established online community such as an online discussion forum
to bait users into responding.[1] They may also plant images and data
on networks that others may find disturbing (usually indirectly
relating to the individual in person) in order to cause confrontation.
While not necessarily related to hacking, such a practice is against
the Computer Misuse Act 1990 in the United Kingdom, where mischief is
caused in order to ensure chaos is spread.

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