An ontology for the Internet of Things provides all the necessary semantics for the specification of IoT devices as well as the specifications of the IoT solution (input, output, control logic) that is deployed using these devices. These semantics include terminology related to sensors and observations, reusing the one already provided by the SSN ontology (by W3C Semantic Sensor Network Incubator Group), and extended to capture also the semantics of devices beyond sensors — i.e. actuators, identity devices (tags), embedded devices, and of course the semantics of the devices and things that are observed by sensors, that change their status by actuators, that are attached to identity tags, etc.