World Wide Web

According to the Eleventh Doctor, human souls were "trapped like flies in the World Wide Web" in the 21st century. The World Wide Web was accessed through Wi-Fi, which the Great Intelligence inhabited. (TV: The Bells of Saint John) Clark Goodman saw the Web as a sign of humanity's psychological debt to spiders. (AUDIO: Worldwide Web)

By 2600, the Galaxy Wide Web was the World Wide Web's intergalactic equivalent. (PROSE: The Dead Men Diaries)

Behind the scenes
According to Tim Foley, writer of of 9 to 5, "Doctor Who invented the Internet" in 1966 when WOTAN was introduced in The War Machines. In fact, director Barnaby Edwards revealed in behind-the-scenes material to that story that he had once sent a copy of The War Machines to, inventor of the World Wide Web, who replied in an email, "I am a fraud." (BFX: 9 to 5)