# Cache A cache is a temporary storage layer that holds copies of frequently accessed data so that future requests for that data can be served more quickly. Caches exist at many levels of a system: in-browser caches, CDN edge caches, application-level caches (such as Redis or Memcached), and CPU caches. Caching reduces latency and backend load by avoiding repeated computation or data retrieval for the same request. Cache strategies include time-based expiration (TTL), cache invalidation on write, and stale-while-revalidate patterns. The choice of strategy depends on how frequently the underlying data changes and how tolerant the application is of stale responses. In API gateway architectures, response caching is a common feature. The gateway can cache responses from backend services and serve them directly for subsequent identical requests. This is especially useful in serverless deployments where reducing cold starts and function invocations directly lowers cost and improves response times. --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://docs.serverlessapigateway.com/glossary/c/cache.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.