Jingle bells is, in my opinion, the most quintessential Christmas song. Created by James Lord Pierpoint, an American songwriter, the song first started to bloom in the mid 19th century. It features an infectious rhythm that is bound to get anybody moving, and it has been for almost 150 years.
The 12 Days of Christmas is an English Christmas carol that consists of lyrics that describe a recipient of gifts that increasing get more and more grand for 12 days. It is also an utter classic of a song that has been heard for many generations and will likely be heard for generations after.
Mariah Carey's All I Want for Christmas is You is easily the most popular Christmas song in modern history. It is the only modern Christmas song that most would include with the likes of the aforementioned and classic Jingle Bells and 12 Days of Christmas, which I would like to add are over a century old at this point.