What is GraphQL (Graph Query Language)?

About

GraphQL is a graph-based, schema-based, SQL-like query language where

queries
returns a tree of data (json objects)
that should match a front-end view,
regardless of where that data was pulled from.

GraphQL is intended to be a replacement for REST APIs and soap api

It covers:

tree-based read-queries,
mutations for updates
and subscriptions for live updates.

Components

GraphQL consists of:

a type system (schema definition),
query language and execution semantics,
static validation,
and type introspection (sort of Wsdl)

Cdn

https://cdnjs.com/libraries/graphiql

Documentation / Reference