AskApache - Caching Tutorial for Webmasters 5. If an representation is stale, the origin server will be asked to validate it, or tell the cache whether the copy that it has is still good.
Together, freshness and validation are the most important ways that a cache works with content. A fresh r What's a Web Cache? Why do people use them? Kinds of Web Caches Browser Caches Proxy Caches Aren't Web Caches bad for me? Why should I help them? How Web Caches Work How (and how not) to Control Caches HTML Meta Tags vs. htaccesswebmaster in Public bookmarkswith etaglast-modifiedif-matchcachefreshstaleproxysquidexpirycachesheadersexpires