Herobrine is the subject of a community-made "creepy-pasta". He is a human entity, but with white eyes, and often described as a dead miner. Herobrine is not a character, but rather superstition. Notch said he was never implemented, saying Herobrine was removed in the 1.6.6 through 1.9 final release and a subtle to stop the skins that have been made of him.

In a possible attempt to scare people, the story raised high amounts of commotion on forums, but was later revealed as a prank of the popular forum and website, 4chan.org.
Summon Herobrine

What must be built to summon Herobrine, in the Herobrine Mod

Stories like this are called "creepy pastas", stories made to scare the reader while they read them late at night.

There are accounts of phantom players without name plates, but these are more probable to be just mob glitches. It was said, however, that Herobrine would appear in two different "forms". One was the "Stalker", Herobrine would have stalked the player, and the player would be able to see Herobrine if the person places his or her render distance to "tiny". Once spotted, Herobrine would disappear. Another was the "Dead Constructor". He would create various different hints of where he is, such as trees with no leaves, gigantic pyramids and 2x2 tunnels, both lit with redstone torches

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