First there was the folk Bob Dylan. Then came the electric Bob Dylan. And it all happened one night at the Newport Folk Festival. The date was July 25, 1965.
In the clip below, you can see how the transition was received. In a word, not well. Appearing in front of a folk audience that lamented the rise of rock, Dylan hit the stage with his electric band and played three songs, including "Like a Rolling Stone." Much of the crowd reacted violently (you can hear it at the end of the clip), and Pete Seeger, the folk legend, raged backstage: "Get that distortion out of his voice ... It's terrible. If I had an axe, I'd chop the microphone cable right now." After his short set, Dylan tried to exit the stage. But, as you'll see, he was coaxed back, with acoustic guitar in hand, to give the people what they wanted - an excellent version of It's All Over Now, Baby Blue. For more on this controversy (which the music world eventually got over), check out Martin Scorsese's documentary "No Direction Home" as well as this Wikipedia entry.