The document discusses GraphQL and its advantages over REST APIs. It provides an overview of GraphQL, describing it as a declarative and compositional query language that allows clients to get precisely the data they need from existing data sources in a single request. The document also includes examples of GraphQL queries and mutations, describes how to define a GraphQL schema, and discusses benefits like flexibility and being self-documenting. Additionally, it mentions the Spring Boot Starter for GraphQL and provides a link to a demo.