"Auld Lang Syne" (Scots pronunciation: [ˈɔːl(d) lɑŋˈsəin]: note "s" rather than "z")[1] is a Scots poem written by Robert Burns in 1788[2][3] and set to the tune of a traditional folk song (Roud # 6294). It is well known in many countries, especially in the English-speaking world, its traditional use being to bid farewell to the old year at the stroke of midnight.

I've always liked this song and wondered what the hell it meant...

The title of the Scottish tune translates to "times gone by" and is about remembering friends from the past and not letting them be forgotten.

Despite its strong association with New Year's Eve, "Auld Lang Syne," written by Robert Burns in the 1700s, was never intended to be a holiday song. Guy Lombardo is credited with popularizing the song when his band used it as a segue between two radio programs during a live performance at the Roosevelt Hotel in New York in 1929. By coincidence, they played "Auld Lang Syne" just after the clock hit midnight, and a New Year's tradition was born.