Your Buddy: "It'll be ok, just put on your cool face"
*Cop knocks on window*
Cop: "License and registration pl-"
You: "Problem, officer?
Cop: "Get the fuck out of here"
So cool in fact the face is grinning while smiling and while half winking and while almost appearing to say "something"
Usually the face is shown saying what amounts to "something wrong?" giving the amazing coolness in the face, and complete lack of any display of guilt any person to question someone with such a face is overcome with a sense of this person is too 'cool' which causes the person looking at the cool face to feel inadequate, and in all cases results in that person telling them to "get the fuck out of here"
While the origin of the cool face is unknown, it is believed to have first surfaced on 4chan, it is most likely a self portrait of the creator, originally made for an avatar
Something Wrong Officer?
Get the fuck outta here!
Not to be confused with the trollface.
Troll1: *rolls down window*
Cop: "Son, do you know how f-"
Troll1: *coolface* "Problem, officer?"
Cop: Get the fuck out of here.