Dark Net is an umbrella term describing the portions of the Internet purposefully not open to public view or hidden networks whose architecture is superimposed on that of the Internet.
"Darknet" is often associated with the encrypted part of the Internet called Tor network where illicit trading takes place such as the infamous online drug bazaar called Silk Road.
It is also considered part of the Deep Web. Anonymous communication between whistle-blowers, journalists and news organisations is facilitated by the "Darknet" Tor network through use of applications including SecureDrop.