A Wireless Sensor Network is a network of wireless sensors.

The sensor nodes are low cost, low power and low size. This adds the aspect that sensor nodes are usually highly constrained computing devices, with very simple capabilities.

The power of a wireless sensor network comes from the combined work of the whole network, allowing environmental monitoring and other functions which have yet to be realised.

Wireless sensors usually take sensor readings and forward them hop-by-hop towards a 'sink', which is usually a more general computer such as a laptop. At each sensor, and along the way, the network can perform intelligent functionality such as aggregation and filtering.

Special programming approaches are required, not only to make the best use of the limited computational power, but also to limit use of the power suuply and network bandwidth.

Eventually wireless sensor nodes will become so cheap that they will be able to be viably deployed in quantities of thousands to monitor environmental conditions and other useful functionality.

Wireless sensor networks are a highly active research area, and this is predicted to continue as new applications are conceived.