Pi Day is an annual celebration of the mathematical constant pi. Pi Day is observed on March 14 (3/14 in the month/day format) since 3, 1, and 4 are the first three significant figures of ?. It was founded in 1988 by Larry Shaw, an employee of the Exploratorium. Celebrations often involve eating pie or holding pi recitation competitions. In 2009, the United States House of Representatives supported the designation of Pi Day.
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