 A precursor to the electric doorbell, specifically a bell that could be rung at a distance via an electric wire, was invented by Joseph Henry around 1831.By the early 1900s, electric doorbells had become commonplace.In most wired systems, a button on the outside next to the door, located around the height of the doorknob, activates a signaling device (usually a chime, bell, or buzzer) inside the building.