# Al-Khwarizmi

Muḥammad ibn Mūsā al-Khwārizmī

A stamp issued September 6, 1983 in the Soviet Union, commemorating al-Khwārizmī's (approximate) 1200th birthday.
Born c. 780
Died c. 850

Muḥammad ibn Mūsā al-Khwārizmī (Persian: محمد بن موسى خوارزمی, Arabic: محمد بن موسى الخوارزمي) was a Persian Muslim mathematician and astronomer. He was believed to have been born around 800 CE and died in 850 CE during the Abbasid Empire,[1] in the Middle Ages. Al-Khwarizmi was known for the book he wrote about algebra, Compendious Book on Calculation by Completion and Balancing.[1] He also wrote a book which taught the Western world about Hindu numerals and how to use them.[2] This book was later titled the Hindu Art of Reckoning.[1] With his books, al-Khwarizmi authored astronomical tables- tables designed to calculate the position of planets or eclipses.[2] Al-Khwarizmi studied and worked during the first half of the 9th century. His work changed the understanding and knowledge of mathematics in the Middle Ages and mathematicians in Europe read his book. They began to use these Hindu–Arabic numerals (0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, ...) instead of the Roman numerals (I, II, III, IV, V, VI, VII, VIII, IX, X, ...). The Arabic numeral system is easier to do mathematics with, as Roman numbers have no place values. This means that they can only deal with whole numbers and do simple equations. Roman numerals also have no number zero.

He wrote a book on Algebra named Al-Jabr Wal' Muqibla in which he introduced his own number system and also introduced Arabic numerals. His books were translated into Greek and Latin. They named his books "So said Algorizmi". The word Algorithm is derived from the word Algorizmi. The word algebra comes from the word al-jabr[3] that is at the beginning of the title of the book. Muhammad ibn Musa al-Khwarizmi worked at the House of Wisdom, where people worked on translating scientific works.

A page from al-Khwārizmī's Algebra

## References

1. Sizgorich, Tom. "al-Khwarizmi." World History: Ancient and Medieval Eras. ABC-CLIO, 2013. Web. 27 Feb. 2013.
2. "al-Khwarizmi." Notable Mathematicians. Gale, 2008. Biography In Context. Web. 27 Feb. 2013.
3. Katz, Victor J. "Al-Khwarizmi." World Book Advanced. World Book, 2013. Web. 27 Feb.