Tor (used to stand for " The Onion Router ", but it's no longer considered an abbreviation, so it's just " Tor "), is an anonymity network, used to surf the web (and more) anonymously. Basically, anyone running the Tor software on their computer runs a proxy, and traffic gets passed (encrypted) from one person running Tor to another person running Tor, multiple times through many users, until it get's to the page that you requested. Hence the term " Onion " used to describe it, since it works in " layers ". Each person running Tor on their computer is called a " Node ". To the page (and anyone logging requests to that page, such as the website owner for example) they can only see the IP address of the last Node (called the "end node"). Any communication along the way, between you, when you request the website page, and the final destination, is encrypted, and cannot be analyzed. However, the last Node in the chain...