Tor is a decentralized network that anonymizes users' web traffic by encrypting it and routing it through a series of relays before it reaches its final destination.
Originally named The Onion Router, Tor is a decentralized network that ensures anonymity by encrypting internet traffic and routing it through a series of servers before reaching its final destination. The network also uses its own ".onion" domain through which users can provide access to websites and services that can only be reached via the Tor network. It is maintained by the nonprofit Tor Project, which has also released Tor Browser — an open-source internet browser that automatically routes traffic through Tor.
The Tor network works by routing each user's traffic through three random nodes, or relays, before transmitting it to its endpoint. Each step of the journey is independently encrypted, and each relay is only aware of where the traffic came from immediately prior and where it is going directly afterward, meaning that by design, no node can ever know the complete path of any traffic.
The network is perhaps most widely known for its use as a gateway to dark web sites and marketplaces accessible through ".onion" addresses. The most infamous of these marketplaces was the now-shuttered Silk Road, where users could anonymously purchase illicit goods such as drugs and fake driver's licenses with Bitcoin (BTC). However, Tor is also used by journalists, activists, dissidents, law enforcement agencies, intelligence services and others who need to remain anonymous online to ensure their safety and security.