Long before calculators and computers were invented, if humans wanted to keep a record of things they had counted, they cut lines into sticks or bones. One of the earliest known examples of this kind of counting was discovered in a cave in South Africa. It was a baboon bone with 29 lines scratched into it. Tests show that the scratches were made about 35,000 years ago.
Tally-Ho!
These lines, or tallies, may have been used to count anything from animals to people or passing days.
At first, the only number symbol used was ‘1’. Really these were just scratches on bones though, so, if humans wanted to count to 1,000, they would have had to find a load of baboon bones and scratch 1,000 1s.
Today, there are 10 different digits, or numerals – 0, 1, 2, 3, 4, 5, 6, 7, 8 and 9. These digits make up what is called the decimal system – from the Latin word for ten: decimus.
The decimal system is a very logical way for humans to count – most people first learn about numbers when they start to count on their ten fingers. In fact, the word ‘digit’ also means ‘finger’. It’s probably how you learned to count and it’s probably just how ancient humans started, too.
The earliest known counting system based on the number 10 was used 5,000 years ago, in Egypt. The Egyptians used sets of lines for numbers up to nine. They looked something like this:
Their new symbol for 10 was 
, and larger numbers used combinations of 
s and s. So 22 was written: . For 100 they used 
and for 1,000 
, up to a million: 
.
A million seemed so massive to the Ancient Egyptians that it also meant ‘any enormous number’.
Timeless Numerals
The Romans also counted in tens, using letters for numbers: I (1), V (5), X (10), L (50) and C (100). Later, D (500) and M (1,000) were added.
To write a number, letters were grouped together, and added up, or taken away, according to the order. For example, if 1 is placed in front of a letter representing a larger number, it means ‘one less than’. IX is 9, or one less than ten. The symbols CL were used to write 150 – or 100 plus 50. So added together the letters CCLVII stand for 257.
You can see Roman numerals on some clocks or at the end of some TV programmes, to show when they were made.
