Page 42 - Curriculum Visions Dynamic Book

Armor
Armor is a key resource for any fighting force. Wars have been won and lost entirely due to superior or inferior armor. Metal armor has always been expensive, and in ancient times only very wealthy peoples could afford it.
The Greeks and Romans used armor in the form of small plates. The alternative was armor made of small loops, called chain mail.
The Romans were one of the first peoples to give their fighting soldiers (and not just their generals) body armor. But soon chain mail became available to the peoples beyond the empire.
The earliest body armor protected the head (in the form of a helmet) and the body in the form of breastplates and back plates. However, after Roman times the metal plates were dropped in favour of coats made of chain mail.
They were all designed to protect the wearer from the slashing effect of a sword (swords were not designed to skewer but to slice). Nobles then sought extra protection in the form of a shield.
Full armor plating developed after chain mail, probably by about 1200. At first it was used on top of the chain mail to protect areas such as elbows and knees. In time the plated armor became sufficiently strong that it could be used instead of chain mail everywhere except under the arms and between the legs. As a result of better protection, the shield
did not need to be so large, and so it became smaller and easier to use.
The invention of bullets and the use of gunpowder in the 16th and 17th centuries made armor instantly obsolete since bullets could easily go through the thin metal sheet or chain mail.
This was, however, not the end of armor plate. With advances in understanding of metals, special hard mixtures, or alloys, of metals were developed that could even stop modern bullets.
The first widely used modern armor was known as a flak jacket and worn in World War I. It was designed to protect against fragments of exploding shells rather than bullets. It used special alloy steel plates stitched into a fabric vest
Bullets are made of lead (although armor-piercing bullets are made with steel tips). Body armor made of metal has to be strong enough to stop the lead bullet. Body armor made from many layers of nylon or Kevlar® works by causing the soft lead of the bullet to flatten, turning mushroom-shaped. As soon as it is flattened, the energy of the bullet can be spread out among the fibres of the many layers of the vest.
The increase in terrorism in modern times has led to widespread use of body armor by police and security forces, but none of it is made with metal. Metal armor plating continues to be used for vehicles, ships, and planes.
(Below) Modern metal armor is restricted to vehicles, ships, and planes.
42