It"s Pi Day, the day we celebrate the mathematical constant π. This day was chosen because today"s date, March 14, expressed numerically, matches the number"s first digits, 3.14. Pi represents the ratio of a circle"s circumference to its diameter. It can be used to compute the area and circumference of a circle, such as the circles that make up this bridge we"re looking at here in Copenhagen. (Who said math wasn"t useful in the real world?) Many people mark the day with activities based around mathematics—and most also serve pie. We can"t think of a more delicious way to study geometry.
A circular celebration
More Desktop Wallpapers:

Cool water in the Quinault

A day of death and rebirth

Sunburst at Angkor

From pirate port to nature preserve

Castle Frankenstein in Darmstadt, Germany

A plot was afoot

In praise of the pipes

How lovely are your branches

A predator at risk

Put your helmet on, we’re going for a hike

Into the woods

A hermitage with a view

Three cheers for polar bears!

Ponta da Piedade rock formations in Portugal

Siblings that play together…

Vacuum Chamber 5 at Glenn Research Center

The perfect canvas for an ancient text

Celebrating Minnesota’s statehood

Racers pushing past sunflowers in the 2018 Tour de France

A unique elephant encounter in Nantes