Printer toner containers, also known as CARTRIDGES, are essential components of laser printers. They contain the toner powder that is used to create the printed image on paper. CARTRIDGES come in a variety of sizes and shapes, depending on the type of printer they are designed for. They are usually made of plastic and contain a small amount of toner powder. The toner powder is transferred onto the paper when the printer is activated. CARTRIDGES must be replaced periodically in order to maintain the quality of the printed image.