An NPC claimed to haunt minecraft.
Then and again, the awesome works of Notch and a few guys has uncovered this hoax.
Herobrine is just a retexture of the default character skin in minecraft (with white eyes.)
He's very creepy, and just runs away after staring at you.
Players claim to have seen him and after attempting to stalk him, they see his works of art.
Herobrine is obsessed with small pyramids in minecraft and 4x4 holes.
He was programmed to dig mini tunnels and make holes on walls.
Being a real scare to players in minecraft, some mod-makers decided to make herobrine mods that spawn herobrine.
Player1: OMG, I just saw Herobrine in my minecraft!
Player2: Lies, he's just a hoax created by Minecraft Devs to scare you.
Player1: STFU, it's true!