The Abacus: Index

Introduction Construction · Basics · Java Applet · Technique · The Abacus Today
History Timeline · Salamis Tablet · Counting Board · Roman Hand Abacus · Suan Pan · Soroban · Schoty · Nepohualtzitzin · Khipu · Lee Abacus
Interactive Abacus Tutor Sarat Chandran and David A. Bagley's incredible Java abacus with a built-in tutor for counting, addition and subtraction.
Calculations Addition · Subtraction · Multiplication & Division · Square Roots · Cube Roots
The Lee Abacus The manual for the Lee Abacus, c. 1958 is available as Text · Images
The Abacus as Art Michael Mode builds exotic abaci as art objects.
Abacus: Mystery of the Bead Abacus Techniques by Totton Heffelfinger & Gary Flom.

Articles, Excerpts and Analysis

The Abacus vs.The Electric Calculator In 1946, a contest held in Tokyo, pitted an abacus against an electric calculator; the abacus won, of course.
Feynman vs. The Abacus Richard Feynman battles against the abacus; the result is not surprising (if you know Feynman).
Comparing the Chinese and the Mesoamerican Abacus An analysis contributed by David B. Kelley.
The Roman Hand-Abacus An analysis contributed by Steve Stephenson.
The Incan Khipu String, and Knot, Theory of Inca Writing by John Noble Wilford. Talking Knots of the Incas by Viviano and Davide Domenici.
Lost Tribes, Lost Knowledge An article about the dangers of forgetting knowledge learned from the past, by Eugene Linden.

Additional Abacus Resources Purchase or build an abacus · An abacus for your Palm · Books about the abacus · Java applet source code · The Mesoamerican abacus
Resources For Teachers The abacus in the classroom · Abacus lesson plan · Math and science resources for teachers
Photos High-resolution photos of my abacus collection.