Body Armor
(or Armour, as we Canadians spell it)
Body armor is divided into two categories: hard and soft.
Hard body armor is similar in concept to armor worn by knights in the medieval era, however it differs significantly in the quality of material used in construction. Medieval armor used iron and fabric. Modern hard armor uses high-grade steel or ceramic (Who would have thought that wearing your mom's china dishes would help you get through a gun fight?) plates and Kevlar fabric. A bullet would punch through medieval armor (as shown in A Connecticut Yankee in King Arthur's Court, by Mark Twain). Bullets tend not to go through modern hard armor, as evidenced by the common name, bulletproof armor. Hard armor covers Category (levels of protection) 3-7, all of which are at least enough to stop a large handgun from a very close range. Category 7 armor is basically a walking tank, and an invitation for someone to shoot you in the head. ("Damn it! Knew I should have sprung for a helmet".)
Soft armor is a little more complex. It works on the principle of the net (as in, a soccer net). Several layers of KEVLAR (essentially a net in itself) are sandwiched between layers of flexible plastic film and resin, all wrapped in a layer of conventional cloth. When a bullet hits the armor, the net absorbs the impact and disperses it over a large portion of the body. Each layer of netting slows the bullet more. Also, the bullet deforms as it hits the armor, changing into a mushroom shape. The impact must be dispersed enough to avoid blunt trauma. The impact would knock you down. Thus, you are left laying on your back with large bruises, but you are alive (see the movie 3000 Miles To Graceland. Kurt Russell wears soft body armor, and it saves his ass, or more properly, his chest, twice.).
Soft armor commonly has pockets in it that allow for ceramic or steel plates to be inserted, for higher protection. Soft armor, without the added plates, cover Categories 1-3, enough to stop small calibre handguns. However, soft armor looks and feels much like normal clothing, so its advantages over hard armor lie in increased flexibility, faster movement and highly increased concealment.
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