What Is The Definition Of Sensor?

The national standard GB7665-87 defines sensors as: "A device or apparatus that can sense the specified measured quantity and convert it into a usable signal according to a certain law (mathematical function law), usually composed of sensitive elements and conversion elements."
The China Internet of Things School-Enterprise Alliance believes that the existence and development of sensors have given objects senses such as touch, taste and smell, making objects slowly come alive. "
"Sensor" is defined in the New Webster Dictionary as: "A device that receives power from one system and usually sends power to a second system in another form."