What does auld lang syne mean? Experts explain lyrics, origin and staying power of the New Year's song

As the clock strikes midnight on New Year's Eve, revelers across the globe will sing "Auld Lang Syne," a song about "old acquaintance be forgot" and, well, other lyrics people may not recall from the New Year's song. 

The song's origins date back to an 18th-century Scottish ballad, with Auld Lang Syne eventually becoming a New Year's celebration staple. Experts explained the song's lyrics, origin and staying power.