Pi Day is an annual celebration of the mathematical constant π (pi) that values 22/7 or 3.14. The day was founded by physicist Larry Shaw in 1988. Today, Pi Day is celebrated in various ways, while some eat pies other organise maths workshops. In 2009, the US House of Representatives passed a resolution to recognise Pi Day. The symbol of Pi was initially used by philologist William Jones in 1706, it was popularised by mathematician Leonhard Euler.
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