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A schema defines a GraphQL API's type system. It describes the complete set of possible data (objects, fields, relationships, everything) that a client can access. Calls from the client are validated and executed against the schema. A client can find information about the schema via introspection. A schema resides on the GraphQL API server. For more information, see "Discovering the Scope GraphQL API."
Field
A field is a unit of data you can retrieve from an object. As the official GraphQL docs say: "The GraphQL query language is basically about selecting fields on objects."
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