# Abu Abdalloh Muhamad ibn Musa al Khorezmi

**(about 783–847)
**Mathematician, astronomer, geographer and historian

Creator of algebra

*Biography*

Muhammad аl Khorezmi a scholar who made an invaluable contribution to the development for world science and made great discoveries. The bibliographical data had not been found. But, there are the facts that at the beginning of 800’s he was invited to Ma’mun ibn Haruna ar-Rashid court, the Baghdad Caliph’s viceroy in Khorasan, and by twenty years old he was well-known scientist, got his education in native Khorazm. In 813 Ma’mun took the throne and together with his scholars that he had gathered around him in Marv moved to Bagdad. Ma’mun was a fan of science. Here, he had founded *Bayt al Hikma *(The House of Wisdom), at the history of science it was named as “Baghdad academy” or “Ma’mun Academy”. Muhammad al Khorazmi was the leader of scientific center to the end of his life. A lot of scholars and scientists from different parts of Central Asia and Arabian East worked there. The richest library of old manuscripts was at their disposal. The observatory had been constructed for works and discoveries.

*Main Scientific Works*

Muhammad al Khorazmi was the author about 20 scientific works that were written in Arabian. Today, only seven of them are available, they are:

*Fi hisab al-hind *(The book on Indian count) -* *an essay, where the decimal positional system with nine digits and zero had been justified and set out.

*Al Kitab al Muhtasarfi hisab al-jabrva al mukabala *(Brief book on algebra and al mukabala)- the work, where algebra was founded as a science by the author and gave its name.

*Zij al Khuarazmi *(Astronomical tables) – an essay, consists of a small theoretical part and tables, where table of trigonometric function of sinus are shown;

*Kitab surat al – ard *(The Book of World Picture) – a geographical tractate, where the description of eastern hemisphere had been shown for the first time in the medieval, the Pacific ocean *(Bahr al Muzallam)* was described, inhabited world map was shown.

*Contribution to the World Science*

Muhammad al Khorazmiy made his contribution to the development of mathematics, astronomy, geography and through them – to the development of civilization:

He founded and he substantiated and coined the decimal positional number system with nine figures and zero sign. Created algebra as a science and gave its name.

He developed and implemented a new method of presenting scientific and educational works – through clear and exact rules. In European literature it is given as “algorithm”, which dates back to the name of al-Khorazmi in Latin transcription. This concept is the basis of all modern digital information and computer technology. Due to this method of exposition, the works of Muhammad al-Khorazmi are widespread. Furthermore, it is known that he is the first who had used polar coordinates.

In the astronomical book of Muhammad al Khorazmi “*Zij”* the movement of the sun, the moon, the five planets, mathematical geographic issues, trigonometry, the eclipses of the Sun and Moon were examined.

In 1126 it was translated into Latin, in 1914 into German and in 1962 into English languages.

*The World Recognition*

Muhammad al-Khorazmi’s merits in the development of mathematics and world civilization are widely recognized, and his name is the only name of the Eastern scientists, is enshrined in the title of “algorithm”, as well as the term “algebra”. Paying tribute to the genius of Al-Khorazmi, the most accurate assessment of his significance in the history of science has given American historian J.Sarton “… is the greatest mathematician of his time, and if we take into account all the circumstances, and one of the greatest scientists of all time.”