A character's armor rating is a measurement of how well protected he/she is against taking damage. For a detailed look on how armor affects damage, see the article on damage. In summary, an increase of armor by 40 will reduce the damage taken by half, while a decrease of armor by 40 will double damage taken. Armor only affects damage taken from weapons or skills that cause physical and elemental damage. Other skills, such as some Monk, Necromancer, and Mesmer skills, will not have their damage reduced by armor. See damage type for more information.