API Caching

API caching is the practice of storing a response temporarily so that subsequent identical requests can be served from the cached copy rather than triggering a new API call. Caching reduces request counts, lowers costs, and decreases response time for end users.

Cache TTL (time-to-live) determines how long a cached response is valid. A product catalog might be cached for an hour; a live hotel availability search might be cached for 30 seconds to balance freshness with performance.

Caching is especially important for high-traffic applications where popular queries are made simultaneously by many users. Caching at the application layer (an in-memory store like Redis) or at the CDN layer can dramatically reduce API request volume without degrading user experience.