The history of the abacus is surprisingly old. Actually, the prototype of the abacus was invented in the Mesopotamia region from 2000 to 3000 BC, but its shape has changed over time, and it is now.
In the Mesopotamia region, there is a trace of the “sand abacus” where a line was drawn on the sand and a stone was placed on the sand.
From about 2300 BC, a line was drawn on the board and a pearl was placed on the line. “Line abacus was used in Greece, Rome, etc. and was used until the 16th century.
A groove abacus was invented, in which a groove was made in a small plate so that it could be carried and a pearl was placed in the groove. It is said that this groove abacus was transmitted to China through the Silk Road from the Middle East and became the current prototype.
Many are made of bronze and are about the size of a palm.
This Sorozo Abacus was used mainly in Rome from around 300 BC to 400 BC.
In China, when the book “Arithmetic Conquest” was published in the original era, two pearls and five abacus abacuses were applied to multiplication and division, and became popular until the end of the Ming era.
At the end of China's Ming era (in the end of the Muromachi period in Japan), the abacus came to Japan through Sakai and Nagasaki, trade ports at that time.
Improvements were made in Japan, and it is now available as an abacus with one pearl and four pearls.