The official definition of GraphQL: A query language for your API. 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. My underdtanding of GraphQL The initial impression of GraphQL to me is that it is one type of SQL language for images, however, this is completely wrong after I read the docs, and I get a better understanding of it by doing some practice. It's not used for picture/images queries, it is just a new open-source data query and manipulation language for APIs, originally developed by facebook. Most of developers know the popular REST API, and there are also other types of API specifications like JSONAPI, SOAP as well. GraphQL query language is used by clients to query data from a GraphQL API service. It's a API query language, not a database query language like SQL. Thus, it doesn't mean that the client uses GraphQL to query data from a database, it queries data from the GraphQL service. It's also a runtime, this means GraphQL can play a role as a server-side service layer for executing the client queries, by using a type system defined for the data. In fact, it isn't tied to any specific database or storage engine and is instead backed by the existing code and data at…