It’s just a high hold favored by competition shooters. It allows for less muzzle flip and faster follow-on shots. Most regular shooters, myself included, use a more traditional hold.
Is this a revolver? I figured it was a semi auto. If it’s a revolver then I can see that position although his fingers on his left hand might get a shot of hot gas from the cylinder leakage. Seen some ugly pics of left hand damaged in just that way.
I don’t recognize the gun. Is it a 22?