And Some More Facts
Additionally, there seems to be a great deal of confusion about the meaning and use of the device. Even though the abacus and counting board (which is also called the abacus by some sources), both were used as aids for counting in the ancient times, they are not the same. In case of counting boards, beads or stones were moved between carved or painted lines to perform calculations. In abacus, on the other hand, beads or stones were slid along the metallic or wooden rods in order to perform these calculations.
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