It's winter, which means many of us are getting into the holiday spirit by sipping on some creamy eggnog. Whether you prefer it spiked, vegan or not at all, it's safe to say the essence of eggnog has become a popular symbol of the holiday season.

But the origin of eggnog dates back further than the expiration date on last week's jug. Here are some shell-shocking facts about of the beloved (and loathed) holiday drink.

Although the exact origin of eggnog is unclear, there are many speculations of where the beverage started. If you do a little research on the internet, you will find a handful of different theories. However, I will list a few that seem to make the most sense. But before we get into a brief history lesson, what is nog and why is it mixed with egg?

The "egg" part is self-explanatory. The "nog" aspect is where things get a little groggy. According to Merriam Webster, nog is "a strong ale formerly brewed in Norfolk England," or in other words, a strong beer. The word nog may also come from the English word, noggin, which is the name of a small drinking cup made from wood. 

It is also believed by many culinary experts that eggnog could have been inspired by the medieval European drink called posset, which is a hot milk and sometime egg based beverage served with figs.

It wasn't until the eighteenth century when the word "eggnog" was used to describe the beverage. A priest named Johnathan Boucher wrote a poem mentioning, "og-drams i' th' morn, or (better still) egg-nogg." 

Let's fast forward to modern times. Your typical eggnog is made with milk or cream, eggs, sugar, and spices, usually nutmeg or cinnamon. Eggnog is also famous for being served with rum or whiskey. However, all of this varies depending on your location on the map. Each region of the world prepares the drink differently.

Although we may never know the genius who put egg with nog, it ultimately paved the way people all over the world celebrate the holiday season. No matter where you live, how you prepare it or what alcohol you mix in, eggnog seems to serve the sole purpose of being able to taste the spice of the holiday season.