una semplice app per aiutarti a imparare e capire questo antico dispositivo di calcolo.

Welcome to Meet the Abacus, a simple app to help you learn and understand the meaning this ancient calculating device. This app is an invaluable aid if you are learning, or if you are just plain curious (like me).

Dating from approx the 2nd century BC.the Chinese abacus, known as the suanpan (which translates as "calculating tray) has a rectangular frame and comes in various widths.

The abacus has two decks of beads and each bead has a value.

There are two beads on each rod in the upper deck and five beads each in the bottom.

The beads are counted by moving them up or down towards the bar, beads moved toward the bar are counted, while those moved away from it are not.

Though designed as a counter, the abacus can be used for functions other than counting, such as multiplication, division, addition and subtraction.