A B a C U S Ka Full Form
Constructions such as the Japanese Soroban have been used for practical calculations up to multi-digit numbers. Each particular abacus design supports multiple calculation methods, including the four basic operations and square and cubic roots. Some of these methods work with unnatural numbers (numbers such as 1.5 and 3⁄4). Learning to calculate with the abacus can improve the ability to calculate mentally. Abacus-based mental calculation (AMC), derived from the abacus, is the act of performing calculations, including addition, subtraction, multiplication, and division, in the mind by manipulating an imaginary abacus. It is a high-level cognitive ability that performs calculations using an efficient algorithm. People who complete long-term AMC training show higher digital memory capacity and experience connected neural pathways more efficiently.   They are able to recover memory to handle complex processes.  CMA involves both visual-spatial and visomotor processing that creates the visual abacus and displaces the imaginary pearls.  Since it only requires the final position of the beads to be stored, it requires less memory and less computational time.
 Russian abacus was used in shops and markets in the former Soviet Union, and its use was taught in most schools until the 1990s.   Even the invention of the Odhner arithmometer mechanical calculator of 1874 had not replaced it in Russia; to Yakov Perelman. It was known that some businessmen who were trying to import calculators into the Russian Empire left desperately after observing an experienced abacus guide.  Similarly, the mass production of Felix arithmometers since 1924 has not significantly reduced abacus use in the Soviet Union.  The Russian abacus did not begin to lose popularity until after the mass production of home microcomputers in 1974. See the full definition of abacus in the dictionary of English language learners The rediscovery of the nepōhualtzintzin is due to the Mexican engineer David Esparza Hidalgo, who, during his travels through Mexico, found various engravings and paintings of this instrument and reconstructed some of them in gold, jade, shell inlays, etc.  The very old Nepōhualtzin are attributed to the Olmec culture, and some bracelets of Mayan origin as well as a variety of shapes and materials in other cultures. A suitable abacus, invented by Tim Cranmer and called Cranmer`s abacus, is often used by visually impaired users. A piece of soft fabric or rubber is placed behind the beads and holds them in place while users handle them. The device is then used to perform the mathematical functions of multiplication, division, addition, subtraction, square root and cubic root.  The word abacus dates back to at least 1387, when a work from Middle English borrowed the word from Latin that described a sand abacus.
The Latin word is derived from the ancient Greek ἄβαξ (abax), which means something without a base and colloquially any piece of rectangular material.    Alternatively, without reference to ancient texts on etymology, it has been suggested that it means “a square tablet strewn with dust” or “drawing board covered with dust (for the use of mathematics)” (the exact form of Latin may reflect the genitive form of the Greek word ἄβακoς (abakos). Although the dust-strewn table is popular, some argue that there is insufficient evidence to support this conclusion.  [Nb 1] Greek ἄβαξ is probably borrowed from a Northwestern Semitic language such as Phoenician, which is related to the Hebrew word ʾābāq (אבק), or “dust” (in the post-biblical sense “sand used as a writing surface”).  Some scholars refer to a figure in the Babylonian cuneiform script that may have been derived from a depiction of the abacus.  Ancient Babylonian scholars such as Ettore Carruccio believe that the ancient Babylonians “may have used the abacus for addition and subtraction operations; However, this primitive device proved difficult to use for more complex calculations.  The Quipu of the Incas was a system of colored knotted ropes used to record numerical data, such as advanced counting sticks – but not to perform calculations. The calculations were made with a Yupana (Quechua for “counting tool”; see figure), which was still used after the conquest of Peru. The principle of operation of a Yupana is unknown, but in 2001 the Italian mathematician De Pasquale proposed an explanation. By comparing the shape of several Yupanas, the researchers found that the calculations were based on the Fibonacci sequence 1, 1, 2, 3, 5 and the powers of 10, 20 and 40 as location values for the different fields of the instrument. The use of the Fibonacci sequence would minimize the number of grains in a field.
 The abacus (plural abacus or abacus), also called counting frame, is a calculation tool used since ancient times. It was used in the ancient Middle East, Europe, China and Russia, centuries before the introduction of the Arabic numbering system.  The exact origin of the abacus is not yet known. It consists of rows of movable beads or similar objects aligned on a thread. They represent numbers. One of the two numbers is set up, and the beads are manipulated to perform an operation such as addition or even a square or cubic root. The complete form of ABACUS is Abundant Beads, Addition and Calculation Utility Systems. It is also known as a counting framework. Some sources mention the use of an abacus called nepohualtzintzin in ancient Aztec culture.  This Mesoamerican abacus used a basic 20- to 5-digit system.  The word Nepōhualtzintzin [nepoːwaɬˈt͡sint͡sin] comes from Nahuatl, formed by the roots; Ne – personally –; pōhual or pōhualli [ˈpoːwalːi] – the report -; and tzintzin [ˈt͡sint͡sin] – similar small elements. Its full meaning has been understood as: Count with similar small elements.
Its use was taught in the Calmecac to the Temalpouhqueh [temaɬˈpoʍkeʔ], who from childhood were students dedicated to recording stories from heaven. Today`s Japanese abacus is a 1:4 type four-pearl abacus, which was introduced from China during the Muromachi period. It takes the form of the upper bridge of a pearl and the four lower pearls. The upper bead on the upper deck was equal to five, and the lower bead is similar to the Chinese or Korean abacus, and the decimal number can be expressed so that the abacus is designed as a one-: four device. Pearls always have the shape of a diamond. Quotient division is usually used instead of the division method; at the same time, to make the multiplication and division numbers consistent, use division multiplication. Later, Japan had a 3:5 abacus called 天三算盤, which is now in the Ize Rongji collection of Shansi Village in Yamagata City. Japan also used a 2:5 abacus. The Chinese abacus, also known as Suanpan (算盤 / 算盘, lit. “computing tray”), is usually 20 cm (8 in.) tall and comes in different widths depending on the operator.
It usually has more than seven stems. There are two beads on each rod in the upper deck and five beads each in the lower deck. Pearls are usually rounded and made of hardwood. Pearls are counted by moving them up or down to the bar; Beads moved in the direction of the beam are counted, while those that move away from it are not counted.  One of the upper pearls is 5, while one of the lower pearls is 1. Each rod has a number below that indicates the value of the place. The Suanpan can be instantly reset to the starting position by moving quickly along the horizontal axis to divert all the beads from the horizontal beam in the middle….