Throughout history, each civilization came up with their own number system to find out how to express quantity. At first, it was just simple markings but as life became complicated, they had to create a system to keep up with everything until it arrived to the ten symbols (0-9) modern civilization is using now. But why does it have to be only these symbols and only ten of them?
The early civilizations of Greek, Hebrew, and Egyptian developed their own system which were just extensions of tally marks. What they did was just add the symbols together and create a new symbol every time a higher number had to be used. Then, the Romans created a new system by subtracting the lower value with the higher value to introduce a new symbol. For example, IV which is 5 -1 to introduce V, and so on.
Despite this, however, using the system still proved to be cumbersome when the number gets higher. According to Allesandra King in her TED Talk presentation about the history of numbers, the beauty and secret of expressing these big numbers come from positional notation, which allows people to re-use the symbols when they express a bigger quantity.
Some of the civilizations that developed this kind of system were the Babylonians, the Aztecs, and the ancient Chinese. In the 8th century, however, Indian mathematicians were able to perfect this type of numbering system. Their ideas spread after Arab conquerors, merchants, and scholars spread them across Europe.
That system was what the modern calls now as the decimal system or the base ten system, represented by ten unique glyphs. The position of each symbol indicates the different powers of ten which starts on the right increasing as it moves towards the left.
However, the key of this number system was the number zero, which was also independently developed by the Mayans. Before zero was included, it was difficult to identify quantities because there was a blank between symbols. For example, it was difficult to identify the difference between 36 and 306 or between 12 and 120. Because of the zero, the numerical notations became more consistent and reliable.
