button in error, pushbuttons are often color-coded to associate them with their function. Commonly used colors are red for stopping the machine or process and green for starting the machine or process. In popular culture, the phrase "the button" (sometimes capitalized) refers to a (usually fictional) button that a military or government leader could press to launch nuclear weapons. Scram and scramble switches Akin to fire alarm switches, some big red buttons, when deployed with suitable visual and audible warnings such as flashing lights and sirens for extreme exigent emergencies, are known as "scram switches" (from the slang term scram, "get out of here"). Generally, such buttons are connected to large scale functions, beyond a regular fire alarm, such as automated shutdown procedures, complete facility power cut, fire suppression like halon release, etc. A variant of this is the scramble switch which triggers an alarm to activate emergent personnel to proactively attend to and go to such disasters. An air raid siren at an air base initiates such action, where the fighter pilots are alerted and "scrambled" to their planes to defend the base. History Push buttons were invented sometime in the late 19th century, certainly no later than 1880. The name came from the French word bouton (something that sticks out), rather than from the kind of buttons used on clothing. The initial public reaction was curiosity mixed with fear, some of which was due to widespread fear of electricity, which was a relatively new technology at the time. See also Event-driven programming Button accordion Button (computing) Keyboard (computing) Panic button Placebo button Push-button telephone Reset button Shutter button Turbo button References Further reading Rachel Plotnick, Power Button: A History of Pleasure, Panic and the Politics of Pushing, MIT Press, 2018, , reviewed in David Trotter, "Making doorbells ring", London Review of Books 22 November 2018 External links Spring Return Button by Sándor Kabai, The Wolfram Demonstrations Project. Human–machine interaction Switches