There are three basic positions for your wrist when gripping a bow. Straight (also called high wrist), neutral and low.

Straight wrist is dropping your hand till the main joint at the base of the thumb is inline with the forearm. That puts the pressure point of your grip entirely in the web between your thumb and forefinger. Very little contact with the grip. The wrist bones are semi-locked in, but not completely, so their is some muscle involvement in keeping the wrist straight. It is not a strong grip and it limits the amount of weight you can draw. However, there is very little contact with the handle and little chance of torquing the bow. It increases your draw length up to an inch.

Low grip is bending your hand up so that the pressure of the grip is fully on the meat of the thumb. The bones of the wrist are locked into their limit of motion so it's a very strong position and let's you draw the maximum amount of weight. Low wrist lowers your draw length by an inch or so. Downside is that there is a LOT of hand contact with the handle and it can be very prone to torque.

Neutral is just that, neutral. You don't bend your wrist at all. Pressure point is still on the web, but it's also spread onto the meat of the thumb. It isn't nearly as consistent because the bones of the wrist are not locked in and the angle of the wrist can float with muscle tension.

Most folks nowadays use the low wrist. 10-15 years ago, high wrist was king. Very few people use the neutral wrist.