What are the rules for handgun safety?

There are many different "standard" sets of safety rules. Here are three:

The Gunsite four basic safety rules are:

1. Treat every gun as if it were loaded.
2. Never point a gun at anything you don't want to shoot.
3. Keep your finger off the trigger until you are ready to shoot.
4. Always be sure of your target and what is beyond it.

The NRA basic safety rules are:

1. Always point the gun in a safe direction
2. Keep your finger off the trigger until you are ready to shoot.
3. Always keep the gun unloaded until ready to use.

The US Military basic firearm safety rules:

1. Assume every weapon you encounter is loaded.
2. Keep the muzzle of your weapon up and down range (pointed away from yourself and other personnel in a safe direction).
3. Keep your weapon safety on until you are ready to fire.
4. Keep your firing finger outside of the trigger housing until you are ready to fire. (this is your second safety)
5. Do not put your weapon on the intended target unless you know what is behind it.
6. Do not put your weapon on the intended target until you are ready to fire.
7. Do not put your weapon on target unless you intend to fire it.
8. When you put your weapon on target, fire.
9. When you fire your weapon, do not pull, flinch, or jerk...breathe and squeeze the trigger.
10. When you have finished firing your weapon, remove the magazine, clear the breach, and ensure all rounds are secured.