**AL-KHORAZMIY**

(dates are unkown)

Abu Abdulloh Mohammad Ibn Musa al-Khorazmiy was
born in Khorezm (Khiva), south-western Uzbekistan. Very little is known about
his early life. The exact dates of his birth and death are also not known,
but it is established that he flourished under halif Al-Mamun in Baghdad through
813-833 and probably died around 840 A.D.

Al-khorazmiy was a mathematician, astronomer and
geographer. He was perhaps one of the greatest mathematicians who ever lived,
as, in fact, he was the founder of several branches and basic concepts of
mathematics. His work on algebra was outstanding, as he not only initiated
the subject in a systematic form but he also developed it to the extent of
giving analytical solutions of linear and quadratic equations, which established
him as the founder of Algebra. The very name Algebra has been derived from
his famous book Al-Jabr va-al-Mifuqabilah. His arithmetic synthesized Greek
and Hindu knowledge and also contained his own contribution of fundamental
importance to mathematics and science.

Thus, he explained the use of zero, a numeral of
fundamental importance developed by the Arabs. Similarly, he developed the
decimal system so that the overall system of numerals 'algorithm' or 'algorizm'
is named after him. In addition to introducing the Indian system of numerals
(now generally known as Arabic numerals), he developed at length several arithmetical
procedures, including operations on fractions. It was through his work that
the system of numerals was first introduced to Arabs and later to Europe,
through its translations in European languages. He developed in detail trigonometric
tables containing the sine functions, which were probably extrapolated to
tangent functions by Maslama. He also perfected the geometric representation
of comic sections and developed the calculus of two errors, which practically
led him to the concept of differentiation. He is also reported to have collaborated
in the degree measurements ordered by Mamun al-Rashid were aimed at measuring
of volume and circumference of the earth.

The development of astronomical tables by him was
a significant contribution to the science of astronomy, on which he also wrote
a book. The contribution of Khorazmiy to geography is also outstanding, in
that he did not only revise Ptolemy's views on geography, but also corrected
them in detail as well as his map of the world. His other contributions include
original work related to clocks, sundials and astrolabes.

Several of his books were translated into Latin
in the early l2th century. In fact, his book on arithmetic, "Kitab al-Jam
'a bil Hisab al-Hindi", was lost in Arabic but survived in a Latin translation.
His book on algebra, "Al-Maqala fi Hisab-al Jabr va-al-Muqabilah",
was also translated into Latin in the l2th century, and it was this translation
which introduced this new science to the West "completely unknown till
then". He astronomical tables were also translated into European languages
and, later, into Chinese. His geography captioned "Kitab Surat-al-Sharq"
, together with its maps, was also translated. In addition, he wrote a book
on the Jewish calendar "Istihhraj Tarikh al-Yahud", and two books
on the astrolabe. He also wrote "Kitab al-Tarikh" and his book on
sun-dials was captioned "Kitab al-Rukhm", but both of them have
been lost.

The influence of Khorazmiy on the growth of science,
in general, and mathematics, astronomy and geography in particular, is well
established in history. Several of his books were readily translated into
a number of other languages, and, in fact, constituted the university text-books
till the l6th century. His approach was systematic and logical, and not only
did he bring together the then prevailing knowledge on various branches of
science, particularly mathematics, but also enriched it through his original
contribution. No doubt he has been held in high repute throughout the centuries
since then.