Well again, starting with a traditional bow, to keep it simple, basically when you are close to your target, the position of your fingers on the string determines, actually where the arrow is going to hit. You're aiming with the arrow. In other words, you're aiming right down the arrow shaft. So, the further down your finger is on the string when you pull up, and pull back and anchor, your arrow is at a higher position. Therefore, it's shooting down at an angle, and into the target.
Now, let's say you move back ten yards, and you want to aim down the arrow, using the point of the arrow again, as your aiming device. You would move your fingers up on the string, maybe just below the arrow, and come up again, pull back to the same position on your face. Now the arrow is at a different angle. It's at a higher angle, so that the trajectory of the arrow will bring the arrow down to the target.
Now, if you want to shoot for even a longer distance, then you would bring your finger above the arrow. Pulling back using the same finger placement on your lip. Now the arrow is at an upper angle, and the trajectory will bring it into the target again from a further distance.
Now, if that distance even increases further, and you want even longer shots, then by placing your finger in a different position on your face, instead of placing it on the lip, placing it under the jaw, that again changes the angle of the arrow and you get a higher trajectory. And again the arrow will fall into the bull's eye.
Of course this would have to be determined by hit and miss. Literally hit and miss, and you determine where you want to place your hand on your face. Now, that's with the re-curve or the traditional bow, with no sight. We have gotten something that works better, more modern. We have what we call a bow sight on the bow. This takes the place of having to move your finger up and down your face in order to determine. All you need to do is set a sight pin on the sight to the distance that you want to shoot at.
For instance, this sight pin on this particular bow, is set up at 20 yards. That means when you pull this bow back and aim through the rear peep, through the rear peep sight, and aim this peep sight into the target, you will hit the target at 20 yards. If you move back to 60 yards, by looking through the peep sight, and placing the lower pin in the target, it will change the angle of the arrow automatically, and that's your 60 yard sight pin. So, you can actually mechanically adjust your sight pins in order to hit the target for longer shots.