Editing Abacus (section)

===Japan===
{{Main|Soroban}}
[[File:Soroban.JPG|thumb|Japanese [[soroban]]]]
In Japan, the abacus is called ''[[soroban]]'' ({{lang|ja|算盤, そろばん}}, lit. "counting tray"). It was imported from China in the 14th century.<ref name=Gul>{{harvnb|Gullberg|1997|p=169}}</ref> It was probably in use by the working class a century or more before the ruling class adopted it, as the class structure obstructed such changes.<ref>{{harvnb|Williams|1997|p=65}}</ref> The 1:4 abacus, which removes the seldom-used second and fifth bead, became popular in the 1940s.

Today's Japanese abacus is a 1:4 type, four-bead abacus, introduced from China in the [[Muromachi period|Muromachi era]]. It adopts the form of the upper deck one bead and the bottom four beads. The top bead on the upper deck was equal to five and the bottom one is similar to the Chinese or Korean abacus, and the decimal number can be expressed, so the abacus is designed as a 1:4 device. The beads are always in the shape of a diamond. The quotient division is generally used instead of the division method; at the same time, in order to make the multiplication and division digits consistently use the division multiplication. Later, Japan had a 3:5 abacus called 天三算盤, which is now in the Ize Rongji collection of Shansi Village in [[Yamagata, Yamagata|Yamagata]] City. Japan also used a 2:5 type abacus.

The four-bead abacus spread, and became common  around the world. Improvements to the Japanese abacus arose in various places. In China, an abacus with an aluminium frame and plastic beads has been used. The file is next to the four beads, and pressing the "clearing" button puts the upper bead in the upper position, and the lower bead in the lower position.

The abacus is still manufactured in Japan, despite the proliferation, practicality, and affordability of pocket [[electronic calculator]]s. The use of the soroban is still taught in Japanese [[primary school]]s as part of [[mathematics]], primarily as an aid to faster mental calculation. Using visual imagery, one can complete a calculation as quickly as with a physical instrument.<ref>{{harvnb|Murray|1982}}</ref>