If you're a fan of made up holidays, today's a day worth celebrating. June 5 is officially National Donut Day — something everyone can get behind — which means you can enjoy free or discounted donuts at restaurants and retailers across the nation.The holiday was created by The Salvation Army in 1938 to honor the women who served up donuts and other treats to soldiers during World War I. It's celebrated annually on the first Friday in June.If you're looking to participate in the sweet celebration of delicious pastries today, there are some very tempting deals from chains you know and love. We've rounded up some of the best freebies and discounts we could find below. Cheers.Dunkin'Dunkin' customers can enjoy a free donut with the purchase of any beverage for National Donut Day for the 16th year in a row.Krispy KremeIt wouldn't be Donut Day without an offer from Krispy Kreme. Customers can get a free donut of their choice in stores on June 5 (with select specialty and limited-time donuts excluded). No purchase necessary. The offer is limited to one donut per person, so don't be greedy! Krispy Kreme is also offering $2 Original Glazed Dozens when customers purchase any regularly priced dozen.