A global network infrastructure, linking physical and virtual objects through the exploitation of  data capture and communication capabilities.

A world wide network of interconnected objects uniquely addressable, based on standard communication protocols

is the network of physical devices, vehicles, home appliances and other items embedded with electronics, software, sensors, actuators, and connectivity which enables these objects to connect and exchange data.

A global network and service infrastructure of variable density and connectivity with self configuring capabilities based on standard and interoperable protocols and formats which consists of heterogeneous things that have identities, physical and virtual attributes, and are seamlessly and securely*intega ed into the Internet.

It is rather a new paradigm that involves a wide set of technologies, applications and visions. It can focus on the virtual identity of the smart objects and their capabilities to interact intelligently with other objects, humans and environments or on the seamless integration between different kinds of objects and networks toward a service oriented architecture of the future Internet.

The Internet of Things: 20th Tyrrhenian Workshop on Digital Communications (Giusto et al.,editors,2010)