Why do we need to use emergency shut down valve

What is ESDV and its uses and purposes, in which place do we use this

ESDV or safety shutdown valve, SDV. Shutdown valve. its purpose is for the opening and closing in case if there is any process fail. Mostly it’s for protection SDV is useful in case of emergency shut down the valve would stop the flow. SDV, ESV, XV, etc… actually it is an On/off valve, Terminology depends on the designer and Clint. Place of use depends upon operation and design, if we can Install a positioner on the valve, we use it as a control valve.