endless doughnut

An ordinary pre-math donut

The same donut, no longer ordinary, post-math.
2 interlocking loops! No seams. Is it magic? Read on.

Impress your friends at the brunch table next Sunday and make this Mobius donut.* If you were paying attention in Geometry in 10th grade, you'd remember the Mobius strip. But if you weren't, here's how to get that knowledge back. Follow the diagram below. via Serious Eats New York

They say the best learning is hands-on.

*You can also do this with a bagel!
Just be sure to use edible marker.