Margaret SANKEY

The heaven and earth design of the abacus has remained unchanged for centuries.
Considered to be the first computer, the abacus has been used since ancient times by a number of civilizations for basic arithmetical calculations. It is still used as a reliable reckoner (and one that does not require electricity or batteries) by merchants and businesspeople in parts of Asia and Africa.
The abacus, or counting plate (suan pan), is