This is traditionally eaten on Burns night, in January, when Scotland's national poet, Robert Burns, is commemorated.
Fair fa' your honest, sonsie face,
Great Chieftan o' the Puddin-race!
Aboon them a' ye tak your place,
Painch, tripe, or thairm:
Weel are ye wordy of a grace
As lang's my arm.
Robert Burns, Address Tae a Haggis
The whole poem and its translation can be found here. And here is an example of an address:


























