Damage is a measure of harm inflicted by the effect of an attack or spell, a weapon, an environmental hazard or another source of injury. Damage is also sometimes used to measure the amount of physical deterioration a vehicle, weapon or other object has suffered, the inanimate equivalent of character health.
Depending on how a roleplaying game tracks health, damage may be expressed as a fixed number, dice pool, or qualitative descriptor. In general, if numerical values are used, higher amounts of damage inflicted bring the sufferer closer to serious injury, unconsciousness or death. If a game uses hit points, damage is usually subtracted from a character's hit point total as they suffer harm.
Some games use different types of damage (cold damage, slashing damage, etc.) to distinguish between sources of injury. This allows for characters to have special rules for interacting with specific types of damage (e.g. ghosts may be immune to non-magical damage). Whilst damage usually measures physical injuries, some games may also track social damage (from reputational harm or community ostracization), or mental damage (from psychic attack or psychological distress). Mental damage may alternatively be tracked with a sanity mechanic or as Corruption.
The amount of damage inflicted by a successful attack may be modified by the attacker's statistics (e.g. Strength), the attacker's weapon, the attacker's degree of success, or the attacker's Advantages. It may also be modified by the defender's statistics (e.g. Constitution), the defender's armor, or the defender's Advantages. Damage may sometimes be modified be expenditure of player resources, either in-fiction resources (ammunition or ablative armor) or metacurrency.
In games that are Powered by the Apocalypse, damage is often alternately referred to as "Harm".