An inkjet cartridge is a small container filled with liquid ink used in inkjet printers. It contains one or more ink reservoirs, which can be black or colored, and is designed to spray tiny droplets of ink onto paper to create text and images. When the printer is activated, the cartridge's print head moves across the paper, releasing ink through tiny nozzles. Over time, cartridges can run out of ink and need to be replaced to maintain print quality. Some cartridges are refillable, while others are designed for single use.