Abacus

thumb|Bi-quinary coded decimal-like abacus representing

350px|thumb|A modern soroban. The right side of the soroban represents the number 1234567890, each column indicating one digit, with the lower beads representing "ones" and the upper beads "fives".

REDIRECT Suanpan#Zhusuan

thumb|Suanpan (the number represented in the picture is 6,302,715,408) thumb|Chinese Abacus thumb|upright=1.35|right|An extended version of a suanpan thumb|right|upright=1.35|A modern 4+1 suanpan (soroban) with a clear-all button thumb|upright=1.35|Suanpan- reincarnation of counting rods The suanpan (), also spelled suan pan or souanpan) is an abacus of Chinese origin. The earliest known written documentation of the Chinese abacus dates to the 2nd century BCE during the Han dynasty, and it was later described in a 190 CE book of the Eastern Han dynasty, namely Supplementary Notes on the Art of

thumb|upright=1.3|The Chisanbop system. When a finger is touching the table, it contributes its corresponding number to a total. Chisanbop or chisenbop (from Korean chi (ji) finger + sanpŏp (sanbeop) calculation 지산법/指算法), sometimes called Fingermath, is a finger counting method used to perform basic mathematical operations. According to The Complete Book of Chisanbop by Hang Young Pai, chisanbop was created in the 1940s in Korea by Sung Jin Pai and revised by his son Hang Young Pai, who brought the system to the United States in 1977.

Abacus found in Salamina

Base-10 portable abacus

system where users mentally visualize an abacus to do calculations