HTML5对link的rel属性添加N多值，其中最有用的就是预加载功能了。它比网上提到图片预加载有时不同，它的加载时机是由浏览器决定的，只有在空闲时间才偷偷加载指定资源，防止一下子加载这么多东西把页面卡死。


下面是MDC的说明
Link prefetching is a browser mechanism, which utilizes browser idle time to download or prefetch documents that the user might visit in the near future. A web page provides a set of prefetching hints to the browser, and after the browser is finished loading the page, it begins silently prefetching specified documents and stores them in its cache. When the user visits one of the prefetched documents, it can be served up quickly out of the browser's cache.

支持浏览器Firefox 3.5+，chrome 13+。

如何使用？

?

<link rel="prefetch" href="http://www.17zouguo.net"> <!-- firefox --> 
<link rel="prerender" href="http://blog.apkbank.net"> <!-- chrome --> 

?当然这不只敢于HTML页面，还可以是图片，JS，HTML等资源。这对于我们加快页面载入速度非常有帮助。