Does Herobrine exist?

I've seen videos of a mob named Herobrine being summoned or randomly encountered. He has the default Minecraft skin but with glowing white eyes. Are these videos all hoaxes or is there a way to summon Herobrine in Minecraft survival mode without mods? Can he be randomly encountered?

Solution 1:

Notch on Twitter is pretty clear on the topic:

I have no plans of adding herobrine.

_Notch

Solution 2:

Short Answer: No.

Long Answer: NO.

And he "removed" him in the 1.6.6 update.

Solution 3:

No. While modding I must have seen every source file since Alpha 1.0_17 a couple of times, and there's simply nothing there. Unless he's an emergent feature of the deepest bowels of the rendering code.