Applications that are data-driven  depend on remote queries that run through APIs. For years, web services have provided basic support for simple query structures. Those services, however, often constrained developers who needed more granular approaches that provided flexibility without creating a huge collection of unnecessary calls. GraphQL—a query language for APIs that was originally built by Facebook—allows developers to choose the kinds of requests they want to make, and receive information on multiple facets of that query in one request. The GraphQL approach to querying across networks can address a wide variety of large-scale development problems. GraphQL enables you to nest multiple request in one query.

In this course, you will learn how to get started with GraphQL step by step learning the basics of this query language,  fetching  data ,handling data,querying schema,creating variable definitions,creating mutations,creating fragments and getting you up to speed with the syntax and vocabulary of GraphQL. The course  explains how to create basic queries, including how to work with arguments and multiple fields. Also you will learn  complex techniques for handling data, including working with aliases, fragments, and pagination. Plus,  how to edit and transform data with mutations.
Topics include:

• Anatomy of a GraphQL Query
• Benefits of GraphQL over REST ApI
• GraphQL Terminology
• Formatting a query
• Passing arguments
• Using Required arguments
• Fetching data with GraphQL Queries
• Creating basic queries
• Using multiple fields
• Understanding schemas
• Handling data
• Drilling down into nested fields with a query
• Adding variables for argument values
• Creating mutations
• Using Aliases
• Using Fragments
• Using multiple variable definitions
• Using nested fields
• Using and creating operation names 
• Using input objects with mutations.