Ammunition is the material fired, scattered, dropped, or detonated from any weapon or weapon system. Ammunition is both expendable weapons (e.g., bombs, missiles, grenades, land mines) and the component parts of other weapons that create the effect on a target (e.g., bullets and warheads).
The purpose of ammunition is to project a force against a selected target to have an effect (usually, but not always, lethal). An example of ammunition is the firearm cartridge, which includes all components required to deliver the weapon effect in a single package. Until the 20th century, black powder was the most common propellant used but has now been replaced in nearly all cases by modern compounds.
Ammunition comes in a great range of sizes and types and is often designed to work only in specific weapons systems. However, there are internationally recognized standards for certain ammunition types (e.g., 5.56×45mm NATO) that enable their use across different weapons and by different users. There are also specific types of ammunition that are designed to have a specialized effect on a target, such as armor-piercing shells and tracer ammunition, used only in certain circumstances. Ammunition is commonly labeled or colored in a specific manner to assist in its identification and to prevent the wrong ammunition types from being used accidentally or inappropriately.
Glossary of firearms terms
A round is a single cartridge containing a projectile, propellant, primer and casing.
A shell is a form of ammunition that is fired by a large caliber cannon or artillery piece. Before the mid-19th century, these shells were usually made of solid materials and relied on kinetic energy to have an effect. However, since that time, they are more often filled with high explosives (see artillery).
A shot refers to a single release of a weapons system. This may involve firing just one round or piece of ammunition (e.g., from a semi-automatic firearm), but can also refer to ammunition types that release a large number of projectiles at the same time (e.