A push-button (also spelled pushbutton) or simply button is a simple switch mechanism to control some aspect of a machine or a process.
This method of linkage is used in simple manual operations in which the machine or process has no electrical circuits for control.
These pushbuttons are called emergency stop buttons and for increased safety are mandated by the electrical code in many jurisdictions.
To avoid an operator from pushing the wrong button in error, pushbuttons are often color-coded to associate them with their function.
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.