The horn button on a motorcycle is a control located on the handlebars that activates the horn to produce an audible sound. This feature is used to alert other road users, signal warnings, or draw attention in various situations. When pressed, the horn button sends an electrical signal to the horn, causing it to emit a loud noise. The placement of the horn button is designed for easy access, allowing riders to quickly and safely use the horn without taking their hands off the handlebars.