Here I quote also the history of the song (quote from Wikipedia)

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Auld Lang Syne History

Robert Burns forwarded a copy of the original song to the Scots Musical Museum with the remark, “The following song, an old song, of the olden times, and which has never been in print, nor even in manuscript until I took it down from an old man’s singing, is enough to recommend any air.” At the time it was very fashionable to claim that one’s own work was “traditional” and one should probably take Burns’ statement with a pinch of salt, and even if some lines of the lyrics were indeed “collected” rather than composed by the poet, it is a fair supposition to attribute the poem as a whole to Burns himself.

There is some doubt if the tune used today is the same one Burns originally intended - but no doubt the melody itself is traditional in the purest sense of the word.

Singing the song on Hogmanay or New Year’s Day very quickly became a Scots custom, which soon spread to other parts of the British Isles. As Scots (not to mention other Britons) emigrated around the world, they took the song with them.

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Auld Lang Syne

Should auld acquaintance be forgot,
and never brought to mind ?
Should auld acquaintance be forgot,
and auld lang syne ?

CHORUS:
For auld lang syne, my dear,
for auld lang syne,
we’ll tak a cup o’ kindness yet,
for auld lang syne.

And surely ye’ll be your pint-stowp !
And surely I’ll be mine !
And we’ll tak a cup o’ kindness yet,
for auld lang syne.

CHORUS

We twa hae run about the braes,
and pou’d the gowans fine ;
But we’ve wander’d mony a weary fit,
sin’ auld lang syne.

CHORUS

We twa hae paidl’d in the burn,
frae morning sun till dine ;
But seas between us braid hae roar’d
sin’ auld lang syne.

CHORUS

And there’s a hand, my trusty fiere !
And gies a hand o’ thine !
And we’ll tak a right gude-willie-waught,
for auld lang syne.

CHORUS
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Links to download Auld Lang Syne

link 1

link 2

link 3