When told to do so (by specific tags in the HTML code), the browser¬† begins silently prefetching specified documents, storing them in its cache.
This is implemented in Firefox, Flock and iCab as far as I know.
The problem with this is that:
- If you are using volume based data plans, the prefetch might generate a lot of unexpected traffic.
- A site might load a malware infected page (called drive-by downloads) without you even knowing it.
- There might be some legal risk for downloading illegal sites without having requested them.
For a more precise explanation see the very complete Wikipedia Article on the topic.
Now, what can we do about that?
Take some easy steps:
- Point your browser to about:config (hit enter and promise to be good 😉
- Go to the network.prefetch-next entry (should be set to true)
- Double-click on the line and the entry should change to false
- You’re done