Cartridge

A cartridge is a single, self-contained unit that combines a supply of material with the means to deliver or utilize it in a device. The term derives from the French cartouche, historically referring to a wrapped or paper container around a powder charge. In modern usage, cartridges are designed to be replaced when their contents are exhausted or spent.

A firearm cartridge typically consists of four components: a metallic case that holds the components together, a propellant charge, a primer to ignite the charge, and a projectile such as a bullet. Modern cartridges are divided into centerfire and rimfire designs, with centerfire the dominant choice for most rifles and handguns. Cartridges vary in case material (mostly brass), case dimensions, and bullet shape and weight, affecting pressure, velocity, and accuracy. The cartridge is sealed before firing; upon ignition, the propellant creates gases that propel the bullet through the barrel. Safety and chambering compatibility are critical.

Printer cartridges come in ink or toner formats. An ink cartridge contains liquid pigment or dye; a toner cartridge holds powdered pigment used in laser printers. Cartridges may be user-replaceable, and some devices use integrated printheads that are replaced at the same time as the cartridge. Color cartridges typically come in cyan, magenta, yellow, and black. Recycling and remanufacturing programs are common due to environmental concerns.

In video games and data storage, a cartridge is a replaceable ROM module that stores software or data for a device or console. Cartridges can include additional hardware, such as memory chips or save batteries. Although optical discs and digital downloads have largely supplanted cartridges in many markets, they remain used in several consoles and specialized devices for reasons of durability and portability.