Armor put on vehicles is usually made of metal and can include one layer over another with open spaces in between (spaced armor) or multiple layers of metal; ceramics (baked clay), and other materials. Another type of armor uses blocks of explosive that explode when another explosion goes off near it. This explosive armor protects by pushing against the other explosion. Vehicle armor is often angled to increase the amount of armor that must be shot through to get inside and to make the shot bounce off rather than piercing the armor.
Tanks have the heaviest armor of all land vehicles. Other military vehicles have armor, but not as much as a tank.
Sometimes armor is put in non-military vehicles, such as limousines used by leaders of a country or by anyone who thinks they might be attacked, e.g. film stars or presidents of major companies.

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