• Plotters are special output devices that use pens to draw on paper. The pens are held in an arm that can move up and down across the paper. The arm and the pen together can draw just like a human but more accurately and quickly. Different colored pens can be used to get colored drawings. Plotters are used by designers and architects since they work with large pieces of paper.

• Plotters are widely used in applications such as computer aided design.

• Pen plotters print by moving a pen or other instrument across the surface of a piece of paper.

• Pen plotters can draw complex line art including text, but they do very slowly because of the mechanical movement of the pens.

• Pen plotters are incapable of creating solid region of color, but can hatch an area by drawing a number of close regular lines.

• This was often the fastest way to produce very large drawings or high resolution art work when computer memory was expensive and processor power was very limited.

• The pens were mounted on a travelling bar whereby the y-axis was represented by the motion up and down the length of the bar and the x-axis was represented by motion of the bar back and forth across the plotting table.

• Plotters are used primarily in technical drawing CAD applications, where they have the advantage of working on very large paper sizes while maintaining high resolution.

• Pen plotters speed is measured by pen speed and acceleration rate, instead of by page printing speed.

• A pen plotter's speed is primarily limited by the type of pen used, so the choice of pen is a key factor in pen plotter output speed.

• Indeed, most modern pen plotters have he commands to control slowing speed depending on the type of pen currently in use