The angle of attack is the direction that the club is heading before contact. In golf instruction, we often use this measurement to look at how solidly you may be hitting the ball. It effects your launch angle, your spin rate, your direction and more.
But in this video, I'm only mentioning the idea of "hitting down" on the ball to keep it simple. If we were to split hairs, you aren't actually hitting down on the ball, but the club head is indeed traveling in a downward direction. But because you will be TURNING your chest and or torso through to the target, the club head will rise up and not crash into the dirt.
The reality is, even though your club must make contact with the turf on which it is sitting, because your weight will be on your front side and you're turning through while posting up, the club will bottom out gently and then travel up.
You know you're doing something wrong if your club is digging trenches into the dirt from 30 yards away...
So check out this little reminder and hit the ball more solidly!