A plotter is a computer hardware device much like a printer that is used for printing vector graphics. Instead of toner, plotters use a pen, pencil, marker, or another writing tool to draw multiple, continuous lines on paper rather than multiple dots, like a traditional printer.  A traditional printer uses a toner to print multiple dots of ink onto the paper or material being used. This can then make straight lines not as clear or straight as they might need to be. A plotter printer, in using a precise tool such as a pencil, and then printing in lines is much more accurate.