Friday, June 3 is National Doughnut Day, a time to indulge in that savory sweet treat with the hole that everyone loves.

However, this isn't just any national holiday: the Salvation Army actually created Doughnut Day in 1938 to honor members of their organization that served doughnuts to World War I soldiers.

Now, nearly 80 years later, Americans and Canadians still mark the occasion with free doughnuts, discounts and giveaways. It's a day to forget the diet and remember just how yummy doughnuts really are.

What is it about the doughnut that's so special, though? Here are five facts about this sugary concoction:

1. Doughnuts Date Back To Prehistoric Times

Although most might consider the doughnut an invention of the 1900s, it's actually been around a lot longer than that. Archaeologists found evidence of fossilized pieces of doughnuts in the middens of ancient Native American settlements. Most historians, though, attribute the doughnut as we know it to the Dutch "olykoeks," a popular treat in New Amsterdam (today's Manhattan).

2. Doughnut Or Donut? Both Are Correct.

People often argue over the correct spelling of the treat. Is it doughnut or donut? The answer is that it's both: although its original name is "doughnut," the shortened version of that name started appearing in the 1800s, although most didn't use that spelling until later, thanks to Dunkin' Donuts.

3. The Original French Version Of The Doughnut Had A Funny Name

In France, the first version of the doughnut was the "pet de nonne," which translates to "nun's farts." Considering that fact, it's surprising that anyone ever ate doughnuts there, but the doughnut is popular all over the world.

4. Boston Has The Most Donut Shops In The World

They might call it Beantown, but maybe they should call it Doughnut Town. The city has the most doughnut shops per capita than anywhere else in the world. It comes down to one doughnut shop for every 2,480 people.

5. Clark Gable Made Doughnut Dunking Fashionable

Dunking doughnuts in milk is a thing, but it didn't become popular until actor Clark Gable demonstrated how to properly dunk a doughnut in 1934's It Happened One Night. He explained to his co-star Claudette Colbert that there was a trick to getting the perfect dunked doughnut.

"Dunking's an art. Don't let it soak so long. A dip and — plop, into your mouth. If you let it soak so long, it'll get soft and fall off. It's all a matter of timing. I ought to write a book about it."