This application allows you to view information on the individual nodes that make up the Tor network. All information is provided by the Onionoo API. You can follow development on GitHub.
Tor is free software for enabling anonymous communication. If you've never used Tor before, it's really easy to use, just download the Tor Browser Bundle and fire it up. If you find Tor useful, maybe consider running a relay.
"Tor" and the "Onion Logo" are registered trademarks of The Tor Project, Inc.