Whenever any computer connects to the net it freely shares information about the address it is using. This is so any data it requests is sent back to the right place.
The Torpark browser has been created by the digital rights group the Electronic Frontier Foundation and uses its own network of net routers to anonymise the traffic people generate when they browse the web.The browser can be put on a flash memory stick so users can turn any PC into an anonymous terminal.
The Tor network tries to stop this information being shared in two ways. First, it encrypts traffic between a computer and the Tor network of routers - this makes it much harder to spy on the traffic and pinpoint who is doing what.
Second, the Tor network regularly changes the net address that someone appears to be browsing from - again this frustrates any attempt to pin a particular browsing session on any individual.
This sort of disruption very quickly skews data used to identify who is doing what and when online.