A mechanical counting device consisting of a frame holding a series of parallel rods on each of which beads are strung. Each bead represents a counting unit, and each rod a place value. The primary purpose of the abacus is not to perform actual computations, but to provide a quick means of storing numbers during a calculation. Abaci were used by the Japanese and Chinese, as well as the Romans.
See also Roman Numerals ,
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Rule
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References Bogomolny, A. "Abacus in Various Number Systems." http://www.cut-the-knot.org/blue/Abacus.shtml . Bogomolny,
A. "Soroban in Various Number Systems." http://www.cut-the-knot.org/Curriculum/Arithmetic/Soroban.shtml . Bogomolny,
A. "Suan pan in Various Number Systems." http://www.cut-the-knot.org/Curriculum/Arithmetic/SuanPan.shtml . Boyer,
C. B. and Merzbach, U. C. "The Abacus and Decimal Fractions."
A
History of Mathematics, 2nd ed. Fernandes,
L. "The Abacus: The Art of Calculating with Beads." http://www.ee.ryerson.ca/~elf/abacus/ . Gardner,
M. "The Abacus." Ch. 18 in Mathematical
Circus: More Puzzles, Games, Paradoxes and Other Mathematical Entertainments from
Scientific American. Heffelfinger,
T. and Flom, G. "The Bean Unbaffled--An Abacus Manual." http://webhome.idirect.com/~totton/abacus/ . Pappas,
T. "The Abacus." In The
Joy of Mathematics. Pullan, J. M. The
History of the Abacus. Smith, D. E.
"Mechanical Aids to Calculation: The Abacus." Ch. 3 §1 in History
of Mathematics, Vol. 2. Yoshino,
Y. The
Japanese Abacus Explained. Referenced on
Wolfram|Alpha Abacus
Cite this as:
Weisstein, Eric W. "Abacus." From MathWorld https://mathworld.wolfram.com/Abacus.html
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