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Protection and security

Personal armour has been worn since the classical period to provide a measure of individual protection, which was also extended to include barding of the mount. The limitations of armour have always been weight and bulk, and its consequent effects on mobility as well as human and animal endurance. By the 18th and 19th centuries, personal armour had been largely discarded, until the re-introduction of helmets during World War I in response to the firepower of artillery. Armoured fighting vehicles proliferated during World War II, and after that war, body armour returned for the infantry, particularly in Western armies. Fortifications, which have been used since ancient times, provide collective protection, and modern examples include entrenchments, roadblocks, barbed wire and minefields. Like obstacles, fortifications are often created by military engineers.