Can good cache control policies really improve my sites performance?
Absolutely. Caching indisputably saves bandwidth and server resources because it reduces network traffic. It does this by reducing the number of round-trips between Web clients and Web servers. This is why shared (proxy) caches exist on the Internet and corporate intranets: infrastructure providers and corporate IT departments make extensive investments in caching technology because the savings are too great to pass up. Improved site performance is simply the other side of this coin. Caching indisputably improves site performance because it reduces network latency. It does this by allowing Web clients to retrieve content from a cache that is located much closer to them than the Web server from which the content originally came. Given normal Web browsing conditions, a cached object will always load faster than an uncached one. Our testing shows that an uncached image can take 0.5 seconds to be verified by an origin server – multiply this lag by the number of images on a page, and your u
