Silly, stupid, or idiotic dramatics that take place in internet interactions between people that would never happen in real life or real person-to-person interaction.
Internet Drama is this:
A acquaintance you have only met through Facebook says, "why are you so retarded?". An acquaintance in real life would never say this. Then you tell your other friends on Facebook and talk bad about the person who said this to you. In real life, this wouldn't happen and no one would give a shit.