WSNPlanet.com

According to WikiPedia, a wireless sensor network (WSN) is a network made of many small sensor nodes (or motes) and one or more base stations (also called sinks), which centralizes the data gathered by sensor nodes.

Sensor nodes are small computers, extremely basic in terms of their interfaces and their components.

Abstract: The availability of cheap, low power, and miniature embedded processors, radios, sensors, and actuators, often integrated on a single chip, is leading to the use of wireless communications and computing for interacting with the physical world in applications such as security and surveillance applications, smart classroom, monitoring of natural habitats and eco-systems, medical monitoring etc. The resulting systems, often called wireless sensor networks, differ considerably from current networked and embedded systems.