What is the difference between REST and GraphQL?

REST (Representational State Transfer) and GraphQL are two different approaches to API design. **REST:** - **Architecture:** Resource-based endpoints (e.g., `/users/:id`). - **Data fetching:** Multiple endpoints can cause over/under-fetching. - **Caching:** Works well with HTTP caching. - **Versioning:** Often via URL or headers. **GraphQL:** - **Architecture:** Query language + runtime with a typed schema. - **Data fetching:** Client asks for exactly what it needs (often one endpoint). - **Versioning:** Typically schema evolution (add fields) instead of `/v2`. - **Caching:** Possible, but often needs client/server strategy. **Key takeaway:** REST is great for simple, cache-friendly APIs; GraphQL shines when clients need flexible, efficient data access across many related resources.