Pré-busca de link no Mozilla :
<!-- full page -->
<link rel="prefetch" href="http://example.org/index.html" />
<!-- an image -->
<link rel="prefetch" href="http://example.org/images/sprite.png" />
Pré-busca de link no Chrome :
<link rel="prerender" href="http://example.org/index.html">
Fonte 1: http://davidwalsh.name/html5-prefetch
Fonte 2: https://developers.google.com/chrome/whitepapers/prerender