The Tor Project is one of the most important organisations on the internet today. It doesn't have the same mainstream name recognition as Google or Facebook, but its work is arguably equally important - providing a way to securely and anonymously browse the internet.
It maintains the Tor network - a global network of computers that gives its users a free and easy way to get online without being tracked. Traffic is routed through a series of relay servers, masking its original location, while the Tor Browser comes with an array of other privacy-centric features.
Tor frequently gets bad press because it can help facilitate online drug dealing and other nefarious activities. But it's also a godsend to activists, dissidents living in authoritarian regimes, journalists - and anyone else who needs to communicate online securely and anonymously.
It debuted in 2002, and was based on technology from the US military. How is it used today? Uncharted, a data visualisation company, has created a map of traffic on the network, Wired reports. By moving the slide, you can see how the traffic flow has changed over time as the network has grown. Double-click or use the buttons to zoom in for a better look.