The Angle of attack or Attack angle refers to the angle at which the club approaches the ball up until impact. The biggest influences on angle of attack are the swing radius, the swing plane and the low point position. Swing radius is the length from club head to center of the player, swing plane is is the height of ur swing (vertically) usually “steep” or “flat”, and the low point position is the lowest point the club head reaches when swinging through the ball.
Creating a proper angle of attack will vary between Irons/Hybrids vs Woods and drivers; but if done correctly you can increase distance in both Irons and woods and give better control with wedges and spin control.
On irons the angle of attack should be negative or in golfer terms hitting down into the ball, vise versa with a driver the attack angle should be positive or in golfer terms hitting up under the ball.
Attack angle is mostly looked at when using a driver because angle of attack with drivers is where most people can lose or gain distance. If you compare two players hitting driver, one with a positive attack angle and one with a negative, both swinging at the same speed, you can find two very important effects to their ball flight. The player with a positive attack angle hit the ball 10-15 yards further but, ended up losing the ball left or right more often then player two who had the negative attack angle, player 2 hit the ball shorter than player1 by 10-15 yards but was able to control the ball better due to higher spin.
Finding the perfect angle of attack with your clubs will help you gain more control with your irons, gain more distance with your driver and help affect the ball flight with every club in your bag.