What is GraphQL?

Schema: Is the center of GraphQL implementation. It describes the functionality available to the clients which are connecting to it.

SDL: Schema Definition Language or SDL is the type system that’s used to define the schema of an API.

Query:  Is an API request made by the client machine application. It supports augments and points to arrays. Query is used to read or fetch values.

Mutation: Is a way to change the dataset in GraphQL. It modifies data in the data store and returns a value. Mutations help you to insert, update, or delete data.

GraphQL and Rest have several differences. Here is a list of the most important. 

Characteristics of Rest:

• Fast client-side requirements are not well suited to Rest's static nature.
• Queries are made at various endpoints (URL).
• Downloading unnecessary information.
• Several endpoints (URL) must be consulted to obtain the information that is being sought.

Characteristics of GraphQL:

• Single endpoint (URL).
• GraphQL uses a strongly typed system to define the capabilities of an API.
• Schemas serve as a contract between the client and the server.
• The frontend and backend can work completely independently.

• GraphQL ORG (main GraphQL website)
• How to GraphQL (videos, articles, infographics)
• GraphQL Cheatsheet (glossary, definitions, infographics)