Light Pen

Light Pen is a computer input device shaped like a pen, used to select or modify data on a computer screen. It contains a photocell that detects light from the screen, allowing users to point, draw, or interact with graphical user interfaces directly on the display.

This tool is primarily for individuals who require precise input for tasks such as graphic design, CAD (Computer-Aided Design), or interactive presentations. It was historically popular with early computing systems and specialized applications requiring direct screen interaction.