GraphQL is a query language for retrieving and manipulating data. Whereas a REST-style API requires multiple queries to return resources, GraphQL is unique in that it can access and return many resources within a single request. It has an effective type system and streamlines data fetching to the client's needs. GraphQL is touted for its usability benefits, and for eliminating over/under fetching concerns. Initially developed by Facebook, GraphQL was opened for public use in 2015. GraphiQL is the official in-browser IDE for GraphQL, helpful for interacting with API calls.