The "Most Sung" Song in the World

It's a little known fact that "Happy Birthday To You" is the "most sung" song in the world. You rarely hear it on television or in movies, because of the copyright. Right?

Well it turns out that the copyright for "Happy Birthday to You" isn't as clear as it seems. There's a long history to it. But the song is missing a copyright renewal, and the original authorship is questionable. Find out more here.