I have a string of 1s and 0s that represents a binary number (e.g. '00101101'). How would I convert that to an actual num? If I use int(), Python assumes decimal and creates a number that's much ...

Unlike our everyday counting system that uses tens, binary uses just two numbers, 0 and 1. Learn more with BBC Bitesize. Suitable for KS3 students.

But, for medium size numbers, the system switches over to binary. The Mangarevans had special words for 10, 20, 40, and 80 — the first few powers of two, multiplied by ten.

But for numbers 20 through 80, they used a binary system, with separate, one-word terms for 20, 40 and 80. For really large numbers, they used powers of 10 up to at least 10 million.

They find that the former Mangarevans combined base-10 representation with a binary system. They had number words for 1 to 10, and then for 10 multiplied by several powers of 2.

The binary system can represent any number using a string of 1s and 0s. Though it is used by computers today, it was first described by the 17th century mathematician Gottfried Leibniz.