In GraphQL, a schema is a blueprint that defines the types, fields, and operations (queries and mutations) that are available to clients. The schema is the contract between the client and the server, specifying what data can be requested and how it can be modified.
A GraphQL schema is defined using the GraphQL Schema Definition Language (SDL), which is a human-readable syntax for defining the structure of a GraphQL API. The SDL includes keywords such as type, query, mutation, field, and argument to define the different components of a schema.
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