Happy Pi Day!
It's March 14, which means today's date matches the first three numbers of the constant ratio of a circle's circumference to its diameter - 3.14, as noted by PiDay.org.
Math geeks mark the day at exactly 1:59 since the longer version of pi is 3.14159....and on and on and on.
As an irrational and transcendental number, pi continues infinitely without repetition or pattern. Some have calculated the number to an extreme - as far as over one trillion digits beyond its decimal point. (You can even locate your birthday in the infinitely long number here.)
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Last year's date, 3/14/2015 was even more significant since the date, with the year, matched the first four digits of pi after the decimal point.
This year may not be as special but as a consolation, some are calling this year the "Rounded Up Pi Day," rounding up those four digits.
Pi Day was started at a San Francisco-based science museum, the Exploratorium, by staff physicist Larry Shaw in 1988. The day gained national recognition in 2009 when the House of Representatives officially noted the day through Resolution 224.
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So what happens on Pi Day? San Francisco's Exploratorium throws its annual pi party, MIT sends out college acceptance notices on the day, and since 3/14 was also Albert Einstein's birthday, people in Princeton, N.J. throw a celebration both in honor Pi Day and the astrophysicist, who lived in the area.
Also, be on the lookout for 3.14 percent discounts in tech products, pizzas and pies.
Incidentally, some people eat pie in celebration of Pi Day, but pies (as in apple or banana cream) actually have a day of their own - National Pie Day - that was on January 23.