Soroban

The soroban (算盤, そろばん^?, counting tray) is an abacus developed in Japan. It is derived from the Chinese suanpan, imported to Japan around 1600.^[1] Like the suanpan, the soroban is still used today, despite the proliferation of practical and affordable pocket electronic calculators.

The soroban's physical resemblance to the Chinese suanpan clearly indicates its origin. The number of beads, however, is similar to the Roman abacus, which had four beads below and one at the top.
Most historians on the soroban agree that it has its roots on the suanpan's importation to Japan via the Korean peninsula in the 15th century.

The methods of addition and subtraction on a soroban are basically the same as the equivalent operations on a suanpan.

Despite the popularity of calculators, the soroban is very much in use today. The Japanese Chamber of Commerce and Industry conducts examinations which soroban users can take to obtain licenses.^[2] There are six levels of mastery, starting from sixth-grade (very skilled) all the way up to first-grade (for those who have completely mastered the use of the soroban). Those obtaining at least a third-grade license are qualified to work in public corporations.