GraphQL is a query language for APIs and a runtime for fulfilling those queries with your existing data. GraphQL provides a complete and understandable description of the data in your API, gives clients the power to ask for exactly what they need and nothing more, makes it easier to evolve APIs over time, and enables powerful developer tools.

With graphql you can query the data you want in one request, rather than multiple for other types of api’s. It was developed by Facebook as an alternative to RESTful architecture, which has been around since 2000.