1. The Fundamental Architectural Difference
REST APIs expose multiple dedicated endpoints (e.g. `/users`, `/posts`, `/comments`), returning fixed JSON structures. GraphQL exposes a single endpoint where clients request precisely the fields they require in a single round-trip.
Key Takeaway: REST provides simplicity and native HTTP caching; GraphQL eliminates over-fetching for complex data graphs.
2. Tradeoffs: Caching, Complexity & Tooling
REST APIs leverage standard HTTP status codes and CDN caching effortlessly. GraphQL simplifies complex nested data queries but requires specialized caching strategies (DataLoader) and introduces query complexity risks.