In the industrial world, a sensor is a device that translates a physical quantity into an electrical quantity, which, once digitized, can be stored, processed and transmitted for use with other information. This enables global operations to be carried out, such as avoiding a disaster, anticipating a problem or optimizing a complex operation.
Before the telecommunications revolution and the development of wireless technologies, the information gathered by a sensor was routed via a costly, cumbersome cabling system, requiring relatively high levels of human effort. The range of uses for sensors remained very limited. To justify the deployment of a sensor network, there had to be a major security issue at stake, or the prospect of significant economic benefits.
Today's new-generation sensors are equipped with "radio" circuits enabling them to transmit and receive information. What's more, they have the memory capacity and computing power to route packets of information. In this way, sensor networks can be formed. They can be self-configuring, self-discovering and relay measured information to their destination. As a result, a large number of applications have been developed to take advantage of this new sensor environment.