A video signal is an electronic signal that transmits visual information, such as images and motion, from one device to another. It can be analog or digital, with analog signals representing video as continuous waves, while digital signals encode video data in binary form. Common formats include HDMI, VGA, and Composite Video. Video signals are essential for displaying content on screens, such as televisions and computer monitors. They carry information about color, brightness, and timing, allowing devices to reproduce images accurately. The quality of a video signal can affect the clarity and detail of the displayed content.