Plier Shaped Nutcrackers
Plier shaped nutcrackers were invented to crack anything hard, which is why this type is used for cracking lobsters and crabs as well as nuts. The nutcracker looks like a pair of pliers with a small curve followed by a larger curve near the top of the nutcracker. These curves have rivets in them to grip the nuts. There is a pivot point after these two curves. An individual places the nut either in the first curve (if the nut is small) or in the second curve (if the nut is medium or large). The individual then squeezes the handles toward each other with enough force to cause the nut to crack open. Only one nut can be cracked at a time.
Character Shaped Nutcrackers
If you have heard of the ballet "The Nutcracker," then you are probably familiar with the character shaped nutcrackers. An individual must pull a lever in the back of the nutcracker down, and then the jaw of the nutcracker opens up. A nut is placed in the mouth of the nutcracker, and the lever is then pushed in the opposite direction. This brings the jaw back up and if done with enough force, the nut cracks under pressure. This often doesn't work as well as the other two types of nutcrackers and is more fun as a decoration.
Screw Shaped Nutcrackers
A screw shaped nutcracker has a small dip in the center bottom where the nut is rested. This nutcracker is wooden. The top of the nutcracker has a screw that is rather large and, again ,made out of wood. Twist the screw to the right until it reaches the nut. Make sure the nut is secure and lined up underneath the screw. Then, continue twisting the screw until enough pressure is put on the nut that it cracks open. You can then peel the rest of the nut apart with your hands.