The abacus, a unique counting tool invented by ancient Chinese people, has faded out in most areas of China, as calculators and computers are widely used in modern times. But in the long history until only twenty years ago, the abacus has long been an important calculation tool for every household, not to mention accountants and dealers.

The abacus is a rectangular wooden frame. Inside the frame, there are usually at least seven vertical rods and a horizontal beam. On each rod there are two rounded beads in the upper deck (each represents five) and five beads at the bottom (each represents one). Each rod represents a different numerical digit. After setting the digit, an operator can move the beads up or down towards the beam to do the calculating. Because of this, abacus computations are also called bead computations. To use the abacus well, one must recite a concise formula by which the calculations of addition, subtraction, multiplication and division can all be simplified into the acts of moving the beads.

It is a joy to watch a skilled hand use an abacus—Beads knock, fingers flutter, and after a few seconds, the result comes out. In the past, in addition to the ability to write elegant brush pen characters, another required skill for businessmen was to use an abacus skillfully. Whenever there was a calculation, there was an abacus. The earliest known written documentation of the Chinese abacus dates to the 2nd century BC (Chinese Han Dynasty). In this way, the beads have been knocking for over two thousand years.