The appropriate response is Electrical Switches. These are electromechanical gadgets that are utilized as a part of electrical circuits to control, recognize when frameworks are outside their working reaches, flag controllers of the whereabouts of machine individuals and work pieces, give a way to manual control of machine and process capacities, control lighting, et cetera.
USB ports, headphone jack/microphone port, and of course, a power button.
Explanation: Well the first one was Plankalkül, but it wasn't implemented untill 1998. But the first to be actually used was Short Code.
Pretty sure answer is <span>E-mail spam</span>
