JSON Schema (http://json-schema.org) is a web standard to define valid JSON objects. The definition is JSON itself and basically describes all properties of an object and their types.
Defining a JSON Schema for your data enables a number of interesting use-cases. Just to name one: For a REST API the JSON content of the requests and replies can be exactly defined (also see OpenAPI) and in addition any JSON can be validated its JSON Schema on the client and server side based on the same definition.
Of course where there is light there is also shadow. With JSON Schema you are required to define your data and the available tooling to do so is not really great (yet). In this presentation we will provide you with criteria to judge whether JSON Schema could be beneficial for your project or is just too much overhead.