Continuity mistake: JD is trying to tempt Turk to do a favor for him with a package of gum. The shot from the front shows JD holding the package with his thumb on the bottom and forefinger on top of the package. The shot switches to over JD's shoulder, and he is now pinching the package on the bottom corner.
Continuity mistake: When Elliot says "That was your best moment" to JD, Turk puts his arm around Carla. When it cuts, he puts his arm around her again.
Answer: This is an American comedian called Scott Thompson, more widely known by his stage name of "Carrot Top".
Tailkinker ★