The size of individual GraphQL query strings can be a major pain point. Apollo Server implements Automatic Persisted Queries (APQ), a technique that greatly improves network performance for GraphQL with zero build-time configuration. A persisted query is an ID or hash that can be sent to the server instead of the entire GraphQL query string. This smaller signature reduces bandwidth utilization and speeds up client loading times. Persisted queries are especially nice paired with GET requests, enabling the browser cache and integration with a CDN.
Automatic persisted queries - Apollo Server - Apollo GraphQL Docs