What is the difference between a piercing gun and a hand clamp? Is the hand clamp a piercing gun?

There are only 2 ways of piercing:

1) Hollow needle. A hollow needle does the piercing and jewelry is then added following the insertion of the needle.

2) Piercing gun/hand clamp: These methods both pierce with the jewelry and there is no needle involved. The hand clamp is a piercing gun without a spring. The force of the hand essentially pushes the earring through the skin vs the "gun" which is spring loaded.