Aside from Pikachu or Link, the Nintendo character you probably recognize the most is Mario. Having debuted back in 1985 with Super Mario Bros. on the Nintendo Entertainment System, the charming Italian plumber has since become one the most widely-known video game characters of all time. With a game library that spans several decades and successive console generations, it's no wonder that Mario has a whole day dedicated to himself in the form of Mario Day.Mario Day was implemented only somewhat recently as far as "international days" go. As the name suggests, Nintendo and gamers alike celebrate Mario and his legacy with events, sales, and announcements. The Mario franchise has plenty to look forward to in the future, including a massive DLC pack for a popular title and a Hollywood live-action adaptation. But why do we celebrate Mario Day in March in the first place?Why is it Mario Day in March?Having initially been implemented as a fan celebration, Nintendo officially began observing "Mario Day" as recently as 2016, according to Evening Standard. The official day takes place on March 10 every year. Why March 10? Simply because the date sort of lines up with the Koopa-stomping plumber's name!\n\nMarch 10 can be written as Mar. 10, or otherwise written as "MAR10". This simple little portmanteau has since become a hallmark date for Nintendo fans and gaming as a whole.Nintendo typically likes to celebrate Mario Day with sales and discounts on some of their Mario-branded titles and products. Otherwise, anyone can celebrate by playing their favorite Mario game or even just talking about how much they love the series!Mario fans have plenty of reason to celebrate, too. The fan-favorite Mario Kart 8 Deluxe on the Nintendo Switch will soon roll out a massive DLC campaign to add over 48 new courses to the game over the next two years. An animated Mario film will also be released by Universal Pictures at the end of 2022, starring Chris Pratt as the popular plumber. This film is not to be confused with the infamous Super Mario Bros., released in 1993.\n\nHappy Mario Day, everyone!