Printer catridge is a removable component in printer.These catridges can be replaced or refilled when the catridge is not giving the great service.There are catridges like ink catridge,toner catridge.Ink catridges are used for inkjet prinrters.Toner catridges are used for laser printers.You can buy these catridges at a cheap rate in remanufacturing companies.The catridges are mainly used in printing.The quality of the print out mainly depends on the catridge. http://www.cheaprefills.info