The term toner is thrown around often on our blog, but really what is the difference between toner and an ink cartridge? Toner is a type of ink that is used in laser printers and copy machines. Toner also comes in a cartridge, but the cartridge is filled with a dry, powdery substance made up of carbon and polymer. The powder is transformed into ink when the machine gives an electric charge and then it melts allowing it to adhere to the surface you are trying to print onto.