Shielding has saved many a life in the Galaxy since it's first inception almost a century ago. It's been compared to the bulletproof vest in terms of saving lives.

Designed to protect the wearer of the armor from any attack at around the speed of sound, it's almost always only useful against bullets, though that speed threshold will help protect against shockwaves from explosions. Each shot drains an amount of energy from the powerful battery. However, the shields will recharge if not hit for a long enough period.

Melee weapons and hits when the wearer isn't aware of the danger will bypass the shields. The reason for this is different among the two sources. Melee attacks are because they are not typically made at a speed that is above the threshold. Sneak attacks are because the user isn't aware of the danger, and hasn't had a chance for it to turn on. (In reality, this is to make sneak attacks viable from a design standpoint.)

Personal shields are built into any standard police issue armor, but a personal shield generator can be bought and installed into a bulletproof vest for a fee.

Large spaceship shields use extreme amounts of power compared to a person, drawing from the fusion generator on the ship. However, they also don't respond to the same level of speed as the personal shielding. This is to prevent unnecessary draw. If it responded to the speeds that personal shields do, the shields would always be taking damage. So, the slug/bullet/round must be moving at an extreme speed, typically in excess of Mach 5. This allows weapons like missiles to bypass, but the missiles move so slowly that it's hard to hit them at any range.