Select printer cartridges based on whether you have an inkjet printer or a laser printer. You should also be aware of cartridge sizes, since these vary from printer to printer.
Inkjet printers are typically used in small offices and at home. They use regular ink and are designed for amateurs. Laser printers are intended for professionals and use a type of powder called toner, which is infused with meltable polymers that transform into ink using the heat of the printer's laser. Inkjet cartridges are not compatible with laser printers and vice versa.
Printer cartridges are sized according to the manufacturer and model of the printer. Find your printer's model number by consulting the manual or by checking the front and sides of the printer.