"Wild World" is a song written by Cat Stevens. It first appeared in his 1970 album, Tea for the Tillerman. It was the most popular single on that album. The song is in the form of the singer's words to his departing lover. Despite having continued feelings that are "breaking [his] heart in two," he accepts her decision and wishes her well, but warns her that life without him will not be so easy. The refrain begins each time with "Oh, baby, baby, it's a wild world / It's hard to get by just upon a smile."

The song has been covered by many artists, with many of the covers becoming hits of their own. As of 2006, the most famous cover of the song is by Jimmy Cliff. Some of the subsequent covers have also been in the reggae style, indicating that they may be covers of Cliff's version, as opposed to direct covers of Cat Stevens' original arrangement.