Tatami (Japanese armour) the other related parts of a full suit of Japanese armour. Collapsible head protection such as "" and other collapsible armor are also "tatami" armor; a traditional kabuto could also be part of a tatami gusoku. Tatami armour was lightweight, portable, convenient for transportation, and they were manufactured inexpensively for the ashigaru light infantry. Tatami armours were worn by all samurai classes from the highest class to the lowest class. The higher class samurai wore elaborate armour while the lower class samurai and retainers wore simpler versions. In his book "Arms and Armor of the Samurai: The History of Weaponry
Armour in Medieval Europe when water-powered trip hammers made the formation of plates faster and cheaper. Also, modern militaries usually do not equip their forces with the best armour available because it would be prohibitively expensive. At times the development of armour has paralleled the development of increasingly effective weaponry on the battlefield, with armourers seeking to create better protection without sacrificing mobility. Well-known armour types in European history include the lorica hamata, lorica squamata, and the lorica segmentata of the Roman legions, the mail hauberk of the early medieval age, and the full steel plate harness worn by later medieval