It is undeniable that the computer is the most popular calculating device in modern society. But how did people calculate in ancient times?
In the long history of civilization, people created various calculating tools. A Chinese invention, the abacus, was the world's oldest and most popular calculator. In China, the abacus is called a 'suanpan'. Little is known about its very early use, but rules on how to use it appear as early as the thirteenth century.
The abacus has endured over time. Even today, the abacus can be seen alongside computers in some banks. Bank employees must pass an abacus examination. Wei Qiang, a clerk of the Communication Bank of China, says the abacus is indispensable to his daily work.
"I think the abacus is more convenient than a computer for small calculations. When you use the computer to calculate, you have to type many extra keys besides the numbers, such as the plus sign and the subtraction sign. But if you use an abacus, you can get the result just by moving its beads.
Since it uses no electricity, has no radiation, and can not be damaged by viruses, the abacus is more reliable than the computer. Actually, it's a good complement to the modern computer."
The common abacus consists of an two decks- upper and lower- separated by a divider. The lower deck has five beads in each column. The upper deck has two beads in each column. Each bead in the upper deck equals 5. Every bead represents a specific figure.
The beads are moved toward the middle beam to represent different numbers. For example, if three beads from the lower deck in the ones column have been moved toward the middle, the abacus shows the number 3. If one bead from the upper deck and three beads from the lower deck in the ones column have been moved to the middle, this equals 5 plus 3, or 8.
The abacus can be read across just as if you were reading a number. To add numbers on the abacus, beads are moved toward the middle. To subtract numbers, beads are moved back to the edges of the frame.
The teaching of calculation with abacus is still popular in Chinese primary schools. Many young students learn calculation through using the abacus, Du Yuzhou is one among them.
"I studied the abacus operation when I was in the kindergarten. Every child in our class had an abacus. It's so easy to do calculations by using an abacus. I get results immediately." Children learn abacus calculation quickly, to their parents' delight. Here's Du Yuzhou's father.
"I found my son became more interested in figures. It's impossible for children at that age to write a formula to do a calculation. The abacus is the best tool to introduce them to primary mathematics."
Throughout education, abacus operation develops into mental calculation. Students figure out calculations in their heads. They get the answer by moving the fictitious beads on the imaginary abacus in their minds.
The abacus has played an important role in China's scientific research. When China developed its first nuclear bomb more than 30 years ago, data was calculated by the abacus.
For some, the collection value of the abacus has surpassed its usage value. An abacus museum recently opened in Nantong, a city in east China's Jiangsu province. Devices made from a variety of materials including gold, jade, bamboo and porcelain are part of its collection.
The largest abacus is more than five meters long and can be operated by several people together. The smallest one is only one centimeter long and is made into a finger ring.
In this modern age when everything can be digitalized and saved on a chip, abacus, the ancient tool, is sometimes more reliable.