Probably in China but variations of it were used throughout the ancient world.
China invented the Abacus.
Charles Babbage developed abacus in 1820 for information send email to sahil2828@gmail.com
Chinese people
The abacus was developed by the Babylonians in 2000 BC. Though mechanical, it is considered to be one of the earliest computers.
You could be thinking of the abacus.
abacus
China invented the abacus .
How did the abacus occur?
The Chinese abacus
An Abacus has beads and strings.
ABACUS
The abacus II!