A drum plotter is a type of printer typically used to produce graphics such as architectural blueprints created with CAD applications. The drum plotter uses a drum to move the paper left and right while one or more pens draw up and down, according to the Chron website. Using more than one pen allows the plotter to draw in different colors.
Another type of plotter is the flatbed plotter. This plotter uses a system where the paper is fixed, and one or more pens move up and down as well as left and right to produce the graphic. By using a drum to move the paper, drum plotters have a smaller footprint than the finished size of the paper.
A different type of plotter, the cutting plotter, replaces the pen with a sharp blade. Instead of printing graphics, this plotter cuts thin materials to produce graphics for signs and advertising. Smaller cutting plotters are available for use in the home, typically for crafts and other hobbies. Laser cutters are beginning to replace cutting plotters due to faster speed, the ability to cut a wider range of materials and increasingly lower prices of the laser cutters.
With advances in printing technology, pen plotters are facing obsolescence. Ink-jet printers are faster and have less complex mechanisms. They are also able to produce any type of graphic, as opposed to pen plotters which only produce line art graphics.