The Janitor is a character on Scrubs played by Neil Flynn.  His real name is unknown and he is simply referred to as the Janitor on the show.  He is constantly lying and torments J.D. every day.

The Janitor Quotes

Janitor: Bull's eye!
J.D.: We're not done with our thing yet, are we.
Janitor: No. For you, it's all just beginning.
J.D.'s Narration: The weird thing is, he was right.

J.D.: Morning, sunshine!
Janitor: I don't like that.
J.D.: Nobody seems to.

Scrubs Quotes

Was she always wearing that big hat?

Dr. Cox

Giddyup, Dr. Dorkian!