Secret codes run the world. The code of life, DNA, is the operating system for all organisms, which spawned intelligent life like us who eventually created codes of our own--language that allows us to talk and the alphabet that lets us write.

The new "Brady Sequence" demonstrates why Fibonacci Numbers are not so special.

5m • Numberphile

In Egypt, professor Marcus du Sautoy uncovers use of a decimal system based on ten fingers of the hand and discovers that the way we tell the time is based on the Babylonian Base 60 number system. In Greece, he looks at the contributions of some of the giants of mathematics including Plato, Archimedes and Pythagoras, who is credited with beginning the transformation of mathematics from a counting tool into the analytical subject of today.

57m • The Story of Maths

When ancient Greece fell into decline, mathematical progress stagnated as Europe entered the Dark Ages, but in the East mathematics reached new heights. Du Sautoy explores how maths helped build imperial China and discovers how the symbol for the number zero was invented in India. He also looks at the Middle Eastern invention of algebra and how mathematicians such as Fibonacci spread Eastern knowledge to the West.

57m • The Story of Maths

A sharp, witty, mind-expanding and exuberant foray into the world of logic with computer scientist Professor Dave Cliff.

59m

An algorithm is a method of solving problems both big and small. Though computers run algorithms constantly, humans can also solve problems with algorithms. David J. Malan explains how algorithms can be used in seemingly simple situations and also complex ones.

4m • TED-Ed

Why are most manhole covers round? Sure it makes them easy to roll, and slide into place in any alignment. But there’s another, more compelling reason, involving a peculiar geometric property of circles and other shapes. Marc Chamberland explains curves of constant width and Barbier’s theorem.

3m • TED-Ed