http://mf34jlghauz5pxjcmdymdqbe5pva4v24logeys446tdrgd5lpsrocmqd.onion/tutorials/to_russia_with_love.html
A circuit is your path through the Tor network. Circuits must consist of at
least two relays, and must end with a relay that allows connections to the
destination you want to reach. Streams by contrast are TCP connections carried over a circuit.