Who wrote the Judy Garland classic song "Over the Rainbow"?

"Over the Rainbow" (often referred to as "Somewhere Over the Rainbow") is a ballad, with music by Harold Arlen and lyrics by Yip Harburg. It was written for the movie The Wizard of Oz (1939) and was sung by actress Judy Garland, in her starring role as Dorothy Gale. The song won the Academy Award for Best Original Song and became Garland's signature song, as well as one of the most enduring standards of the 20th century.

About five minutes into the film, Dorothy sings the song after failing to get her aunt and uncle to listen to her relate an unpleasant incident involving her dog, Toto, and the town spinster, Miss Gulch (Margaret Hamilton). Dorothy's Aunt Em tells her to "find yourself a place where you won't get into any trouble". This prompts Dorothy to walk off by herself, musing to Toto, "'Some place where there isn't any trouble.' Do you suppose there is such a place, Toto? There must be. It's not a place you can get to by a boat, or a train. It's far, far away. Behind the moon, beyond the rain...", at which point she begins singing.