The Onion Router (Tor), is free and open source software that helps you defend against traffic analysis, a form of network surveillance that threatens personal freedom and privacy, confidential business activities and relationships, and state security. Tor has traditionally been a separate full browser, browser add-on, or proxy software which had to be actively added or configured. Purism, using the Trisquel Abrowser, ships with Tor installed by default, so opening up a ‘private window’ within Abrowser will activate Tor. So now good anonymity online is now one private window away!
Tor protects you by bouncing your communications around a distributed network of relays run by volunteers all around the world: it prevents somebody watching your Internet connection from learning what sites you visit, and it prevents the sites you visit from learning your physical location.