The absence or presence of breastplates as a military technology used in warfare. Armor made from wood, horn, or bone can be very important (as in the spread of the Asian War Complex into North America). Leather and cotton (in the Americas) armor was also effective against arrows and warclubs. Breastplate refers to any form of torso protection (in fact, we might rename this variable 'torso protection' at a later date). In the vast majority of cases you will probably find that if a culture has wooden armor, leather armor, chainmail armor, or scaled armor that breastplate should be coded as present because this is the most common location for armor. However, in theory, it is possible to have armor that doesn't protect the torso (for example, a culture might use armor that protects the limbs only).