Celebrating Pi Day 14 Mar 2025

Calculating the ratio of a circle"s circumference to its diameter is as easy as pi. Today is Pi Day, an event that celebrates this mathematical constant. This date was chosen because 3, 1 and 4 are the first three significant figures of pi (π) when it is written out. Pi is an irrational number, which means that it can"t be written as a fraction. When written out, its decimal representation goes on infinitely without repeating. The oldest attempts to calculate pi date back to ancient Babylon and Egypt, around 1,900 BCE.

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Today in History

A beautiful labyrinth
14 Mar 2024Happy Pi Day!

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15 Dec 2024Lake Misurina, Dolomites, Italy
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13 Jan 2024Road to Hana, Maui, Hawaii, USA
A shallow sea
5 Aug 2025Tide pools in La Jolla, California, United States
Where can you find this cute creature?
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27 Jul 2025Barracudas at Shark Reef, Ras Mohammed National Park, Sinai Peninsula, Egypt
Dad on duty
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Poetry in suspense
Guarding the pass
11 Oct 2024Grasmere, Lake District, Cumbria, England