Everyone knows Rudolf. He is Santa's leading reindeer on account of his red nose that lights Santa's way through the winter night sky every Christmas Eve.

However, there is no mention of Rudolf in Clement Clarke Moore's classic poem ''Twas the Night Before Christmas (‘also known as 'A Visit From St Nicholas') written in 1822. More clearly names all of Santa's reindeer –

"Now Dasher! Now Dancer! Now Prancer and Vixen!
On Comet! On Cupid! On Donner and Blitzen!"

But Moore doesn't make any reference to Rudolf. Rudolf is a later addition tot he festive season. The famous Christmas song 'Rudolf the Red Nose Reindeer' was written by Robert L. May originally created as an advertising strategy for the Montgomery Ward Department Store in 1939.

The song depicts the heart-warming tale of the disfigured reindeer. Rudolf has the obvious deformity of a bright red nose. Because of his nose he is ridiculed and cast out from reindeer society.

"All of the other reindeer,
Used to laugh and call him names,
And they wouldn't let poor Rudolf,
Join in any reindeer games."

However, Rudolf's luck changes when Santa sees Rudolf's affliction as an asset and asks Rudolf - "Won't you guide my sleigh tonight?”

This simple but touching story line won the hearts of millions, so much so that Rudolf was added to the festive season as a special companion of Santa.