缓存并不是一个复杂的概念，它指的是：把Ｗｅｂ内 容移到靠近浏览者所在的地方，从而缩小由于网络延迟、服务器负载过重等造成的响应延迟。把Ｗｅｂ内容放入本地硬盘是获得最佳缓存效果的理想方法：如果硬盘有足够大的空间存储整个Ｗｅｂ（或至少存储整个目标网站），就永远不 Caching is not a complicated concept. It refers to moving Web content closer to the viewer’s location to reduce latency due to network latency, server overloading, and so on. Putting the web content into your local hard drive is the best way to get the best cached results: if your hard drive has enough space to store your entire web (or at least the entire destination web site)