The word ‘algorithm’ (Latin “algorithmus”) has been derived as a combination of the word “algorism,” which in the middle ages denoted the art of computing using Arabic numerals, and the Greek word “arithmós” (number). The word “algorism” itself comes from the name of a Persian mathematician Mohammed ibn-Musa al-Khwarizmi (from Khwarizm) who, in the ninth century, described how to perform the four arithmetic operations in the decimal number system.