It don't take money. Don't take fame. Don't need no credit card to ride this train.
That's the power of music, baby.
Like any good soundtrack, the songs in Back To The Future leap out of your speakers, clamber inside your brain and lodge themselves somewhere inside your cerebellum… where they hang out until you can barely stand it any longer.
You've got Alan Silvestri, composer and conductor of the Outatime Orchestra (that's real), providing the title track and all the other intermittent music we associate only with this film; Huey Lewis and the News, responsible for the catchiest tunes, such as The Power of Love and Back in Time; and, of course, all those quintessentially 1950's songs like Earth Angel and Johnny B. Goode. (P.S. Little in-joke with Huey Lewis in the movie: he has a cameo as the guy at Marty's audition in the early scenes. He's the one who tells Marty that his band is "just too darn loud," while the band plays a variant of Lewis's own "The Power of Love.")
Silvestri held the reins, and he must have done a pretty decent job, because Zemeckis hired him to score just about every film he made afterward. The composer even picked up a couple Oscars, one for the score of Forrest Gump and another for Best Song in The Polar Express.
The honors that have been bestowed on him aren't surprising. Just check out the climactic scene toward the end of BTTF when Marty and Doc are trying to tie up loose ends—and wires—to send the former back to 1985… then watch it with the sound turned off. Just looks like a bunch of idiots running around in the dark, doesn't it? The music in this scene is everything.