Tor

Tor is free software that stands for "The Onion Router". It enables anonymous communication by directing Internet traffic through a free, worldwide, volunteer overlay network consisting of thousands of [[frame relay|relays]] to conceal a user's location and usage.

What Tor does is make it hard to trace a user's Internet activity including visits to web sites, newsgroup postings, [[instant messaging]], and social media. What Tor does not do is prevent an online service from determining when it is being accessed, meaning Tor protects a user's privacy but it does not hide the fact that someone is using Tor.

Historical perspective: The Onion Router is the name of the original software project developed in 2002 by Roger Dingledine and Nick Mathewson. Tor's intended use is to protect the privacy of its users and keep their Internet activities from being monitored. The Silk Road website, launched in 2011, shut down in 2013, known as an online black market for selling illegal drugs, operated as a Tor hidden service, so online users were able to browse it anonymously and securely without traffic monitoring.