Developers can use GraphQL in order to create a schema, which

describes all the possible data that clients can query on it.

▪ GraphQL schema is made up of object types, that define which kind

of object you can request and which fields it has.

▪ Client can send queries, GraphQL validates the queries against the

schema then executes the validated queries.

▪ Resolver is a function that attaches to fields in a schema. During

execution, the resolver is called to produce the value.

▪ Mutation is a GraphQL Operation that allows you to insert new data

or modify the existing data on the server-side.

https://www.howtographql.com/basics/2-core-concepts/