Welcome to Orion Context Broker.
Orion is a C++ implementation of the NGSIv2 REST API binding developed as a part of the FIWARE platform.
Orion Context Broker allows you to manage the entire lifecycle of context information including updates, queries, registrations and subscriptions. It is an NGSIv2 server implementation to manage context information and its availability. Using the Orion Context Broker, you are able to create context elements and manage them through updates and queries. In addition, you can subscribe to context information so when some condition occurs (e.g. the context elements have changed) you receive a notification. These usage scenarios and the Orion Context Broker features are described in this documentation.
Github's README.md provides a good documentation summary and API Reference Documentation provides the full API documentation. The User Manual and the Admin Guide cover other specific advanced topics.