Auld Lang Syne is traditionally sung at midnight during New Year's Eve celebrations in many English-speaking countries.
The song is based on a Scots poem associated with Robert Burns and is usually performed to a traditional melody. Its title refers to “old long since,” commonly understood as old times or days gone by. The lyrics ask whether old acquaintances and shared memories should be forgotten, making the song a natural fit for a year-ending ritual.
The tune became especially prominent in New Year's celebrations through twentieth-century broadcasting and popular culture. Guy Lombardo and his orchestra helped establish the song as a familiar midnight feature for American audiences through their nationally broadcast New Year's Eve performances.
It is not an official anthem of the United States or of every English-speaking country. Local traditions vary, and the song may be sung at other farewells, memorials, graduations, and closing ceremonies.