preferable to Expires, but it may not hurt to set both values. The most effective solution is to change any links to them; that way, completely new representations will be loaded fresh from the origin server. This is necessary if the item has been changed on the origin server and having an outdated item in cache would cause significant issues for the client. This is not necessarily true; the http specification does not set any guidelines for Pragma response headers; instead, Pragma request headers (the headers that a browser sends to a server) are discussed. If you serve the same content on different pages, to different users, or from different sites, it should use the same URL. Web caching, the focus of this guide, is a different type of cache.
Check your pages with REDbot it can help you apply many of the concepts in this tutorial. Consult your Telnet clients documentation. There are two main reasons that Web caches are used: To reduce latency, because the request is satisfied from the cache (which is closer to the client) instead of the origin server, it takes less joyas voladoras brian doyle essay time for it to get the representation and display. Unfortunately for them, even if Web caches didnt exist, there are too many variables on the Internet to assure that theyll be able to get an accurate picture of how users see their site. This means that all the keywords must be found in a page for it to be included in search results.