## Quick Reference

(*c.*800–c. 847) Mathematician, astronomer, and geographer

With my two algorithms, one can solve all problems – without error, if God wills it!—*Algebra* Little is known about the life of Al-Khwarizmi (al‐kwah‐riz‐mee). It is thought that he took his name from his birthplace, Khwarizm – then part of the Persian Empire, now Khiva in Uzbekistan. He was a member of the academy of sciences in Baghdad, which flourished during the rule (813–33) of caliph al-Ma’mun. Although probably Persian, he is often described as an Arab mathematician because he wrote in Arabic and did all his work in the context of 9th century Arab Abbasid culture.

With my two algorithms, one can solve all problems – without error, if God wills it!—*Algebra*

Al-Khwarizmi’s main astronomical treatise and his chief mathematical work, the Algebra, are dedicated to the caliph. The Algebra enlarged upon the work of Diophantus and is largely concerned with methods for solving practical computational problems, rather than algebra as the term is now understood. Insofar as he did discuss algebra, al-Khwarizmi confined his work to equations of the first and second degrees. Similarly, his astronomical work, Zij al-sindhind, is also based on the work of other scientists. As with the Algebra, its chief interest is as the earliest work still in existence in Arabic. Al-Khwarizmi's other main surviving works are a treatise on the Hindu system of numerals and a treatise on geography. The Hindu number system, with its incorporation of a symbol for zero, was introduced to Europe via a Latin translation (De numero indorum; On the Hindu Art of Reckoning) of al-Khwarizmi’s work. Only the Latin translation remains but it seems very likely that al-Khwarizmi was the first mathematician to expound the new number system systematically in Arabic. The term “algorithm” (a rule of calculation) is a variant form of his name. His geographical treatise marked a considerable improvement over earlier work, notably in correcting some of the influential errors and misconceptions that had gained currency owing to Ptolemy's Geography.

*Subjects:*
Science and Mathematics.