Thursday is National Sandwich Day, a celebration of the American staple.  The holiday is celebrated on Nov. 3 to commemorate the 293rd birthday of John Montagu, the Fourth Earl of Sandwich. Montagu is credited with inventing the concept behind the sandwich, two pieces of sliced bread with lunch meat fillings.

According to sandwich legend, the 18th century English noble was a prolific gambler. During one 24-hour gambling tournament, Montagu supposedly requested that his servants bring him two slices of bread with lunch meat between them, so that he could hold his lunch in one hand without getting his cards greasy.

Montagu was known as the Fourth Earl of Sandwich, so his friends began to order the same as Sandwich, giving the lunchtime staple its name.

In the United States today, the peanut butter and jelly sandwich is the most commonly eaten. The PB&J became wildly popular during the Great Depression because the American classic is highly nutritious but also very inexpensive to make. According to Foodbeast.com, a 2002 survey shows that the average American student will have eaten 1,500 peanut butter and jellies before graduating from high school. To see where some other sandwiches come from, check out this sandwich breakdown.

National Sandwich Day will be commemorated in Philadelphia where patrons celebrate with GPTMC's With Love Hoagie Contest. Philadelphians will taste test different sandwiches and the winner will be sold in over 70 PrimoHoagies stores, reported NBC Philadelphia.

What sandwich will you eat today to celebrate this holiday?