The original development calculator is the earliest calculation tool. For example, Quipu or khipu is a method of knotting notes by ancient Incas to count or record history. It is made up of knots of many colors.
There are also ancient Greeks of Antikythera, Chinese abacus and so on. The first calculation tool used in ancient China was called planning, and it was also called calculation. This kind of calculation is made of bamboo, and it is also made of wood. The animal bone acts as a material. A bundle of about 270 pieces can be carried in a bag. The abacus that is still in use today is another invention in the field of ancient Chinese computing tools. The abacus of the Ming Dynasty was almost identical to the modern abacus.
The calculators in the early days of modern development were purely manual, such as abacus and calculation. The abacus is usually made of sliding beads. In the West, abacus was used for centuries before the popularity of Indian Arab numerals, and it is still widely used in accounting and commerce in modern China. A mechanical calculator appeared later. At the beginning of the 17th century, the computing tools of Western countries had a great development. The British mathematician Napier invented the "Napier calculation", and the English pastor Ozard invented the cylindrical logarithmic scale. Can do addition, subtraction, multiplication, division, multiplication, square root calculation, and even trigonometric, exponential and logarithmic functions. These calculation tools not only drive the development of calculators, but also lay a good foundation for the development of modern calculators. Modern society uses a wide range of computing tools.
In 1642, the 19-year-old French great scientist Pascaline invented the first mechanical calculator. In his calculator, there are some interlocking gears. One gear that turns ten will make the other When the gear is turned over, one can dial the number as if the dial is dialed, and the result will appear in another window, but only the addition and subtraction can be done. In 1694, Leibniz improved it in Germany into a calculation that can be multiplied and divided. Since then, it has not been until the late 1950s that electronic calculators appeared.
In the 19th century, Babbage pushed the concept of computational tools forward, trying to create the first programmable calculator, but the machine he built was too heavy to operate.
In the 20th century, in the 1970s, microprocessor technology was absorbed into the calculator process. The original microprocessor was produced by Intel in 1971 for the Japanese company Busicom (ビジコン). In 1972, HP introduced A handheld scientific calculator HP-35.
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