API Rate Limiting Protect APIs from abuse using rate limiting algorithms with per-user and per-endpoint strategies. Algorithms | Algorithm | Pros | Cons | |-----------|------|------| | Token Bucket | Handles bursts, smooth | Memory per user | | Sliding Window | Accurate | Memory intensive | | Fixed Window | Simple | Boundary spikes | Token Bucket (Node.js) Express Middleware Response Headers Tiered Limits | Tier | Requests/Hour | |------|---------------| | Free | 100 | | Pro | 1,000 | | Enterprise | 10,000 | Best Practices - Use Redis for distributed rate limiting - Include proper headers in…