The national standard GB/T 7665-2005 defines a sensor as: "A device or apparatus that can sense a measurand and convert it into a usable output signal according to a certain law, usually composed of a sensing element and a conversion element."
The China Internet of Things Industry-University Alliance believes that the existence and development of sensors have given objects senses such as touch, taste, and smell, gradually making them come alive.
The new Webster's Dictionary defines a sensor as: "A device that receives power from one system and usually transmits power to a second system in another form."