"Auld Lang Syne" (Scots pronunciation: [ˈɔːl(d) lɑŋˈsəin]: note "s" rather than "z") is a Scots-language poem written by Robert Burns in 1788 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 on New Year's Eve. By extension, it is also sung at funerals, graduations, and as a farewell or ending to other occasions. The international Scouting movement in many countries uses it to close jamborees and other functions.
The poem's Scots title may be translated into standard English as "old long since" or, more idiomatically, "long long ago", "days gone by", or "old times". Consequently, "For auld lang syne", as it appears in the first line of the chorus, might be loosely translated as "for the sake of old times".
The phrase "Auld Lang Syne" is also used in similar poems by Robert Ayton (1570–1638), Allan Ramsay (1686–1757), and James Watson (1711), as well as older folk songs predating Burns. Matthew Fitt uses the phrase "in the days of auld lang syne" as the equivalent of "once upon a time" in his retelling of fairy tales in the Scots language.