Some people feel the need to comment on everything—and we're not talking about your aunt who ends every message with "XO from all of us." About 5 percent of people online self-identify as trolls (a.k.a. those annoying commenters who attack anything and everything on the Web). This video from AsapSCIENCE discusses research that found trolls share "dark traits," like narcissism, psychopathy, and sadism. Unfortunately, these people aren't so nice IRL either.

Most of us feel guilty inflicting pain on others, but sadistic people actually enjoy making others suffer. So when you engage with the haters, you're feeding into their nastiness. The more you reply, the harsher the comments will get. So next time you're being trolled, just take a page out of Taylor Swift's book.

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