March 14 represents the first three digits of the mathematical constant 3.14 and falls on Albert Einstein's birthday.

Why is March 14th called Pi Day

Pi Day became an annual Exploratorium tradition that still goes on today, and it didn't take long for the idea to grow exponentially,

Why is March 14th called Pi Day

hitting a peak on March 12, 2009,
Pi Day is celebrated by math fans all around the world – often with pie to celebrate all things pi!

Pi Day is an annual celebration of the mathematical constant π (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 π

In 1988, the earliest known official or large-scale celebration of Pi Day was organized by Larry Shaw at the San Francisco Exploratorium

History

where Shaw worked as a physicist , with staff and public marching around one of its circular spaces, then consuming fruit pies.

History

The Exploratorium continues to hold Pi Day celebrations.
On March 12, 2009, the U.S. House of Representatives passed a non-binding resolution for Pi Day.

History

Pi Day is most frequently March 14, but related celebrations have been held on alternative dates.
Pi Approximation Day is observed on July 22 (22/7 in the day/month format)

Alternative Dates

since the fraction 22⁄7 is a common approximation of π, which is accurate to two decimal places and dates from Archimedes.

Alternative Dates

Two Pi Day, also known as Tau Day for the mathematical constant Tau, which is approximated as 6.28, is observed on June 28 (6/28 in the month/day format)