The Animated Abacus from  

In DomWorld scorekeeping is done using a pair of animated abaci that display in the players' windows whenever scoring occurs. Together with pip-hiliting during scoring, a strong visual impression of how scoring occurs in dominoes is achieved.

Click to see an animated abacus.

abacus [ab´a·kus] A frame holding beaded rods for calculations. The abacus is man's first calculator. In Europe it was the prefered way of doing addition and subtraction until the adoption of hindu-arabic notation over Roman Numerals around the mid 1600's. Like Hindu-Arabic notation, the standard abacus is a place-value system; i.e. symbols have different meanings depending upon position. It differs from the hindu-arabic system in using beads instead of symbols (digits 0 - 9) to represent numbers.

DomWorld's abacus is based upon the Chinese Suan-Pan which emerged in the 1300's. It is perhaps the standard modern form of the abacus. The Suan-Pan uses a five-bead for representing numbers. By using this denominated five-bead the abacus simplifies the operations of addition and subtraction, even when compared to the standard notational methods using Hindu-Arabic numbers. Partly this is due to the need to know fewer arithmetic facts when doing multi-digit arithmetic. The abacus may also ease learning by presenting a more physical representation of the number concept. A physical system might more intuitively represent the concept of equivalence (regrouping). By using the abacus for scorekeeping DomWorld hopes to familiarize the user with the general principles of operation of the abacus.

educational value of the abacus-essay