It is a little known fact that the invention of negative numbers can be traced back to China. Around 200 BC, Chinese mathematicians were working on a system of counting rods, which were used to represent numbers.

They discovered that if they placed a rod upside down, it represented the absence of a number, or a negative number.

This innovation allowed them to solve problems that had previously been unsolvable, and it quickly spread to other cultures.

Today, we use negative numbers in everything from mathematics to finance, and we owe a debt of gratitude to the Chinese mathematicians who first invented them.