I was a mathematician and an astronomer in Al-Mamum's "House of Wisdom," located in Baghdad.
In addition to books containing astronomical tables, I wrote two books on algebra and arithmetic, which used the Hindu numerals that eventually spread to Europe.
The word "algebra" is derived from my book Al-jabr wa'l muqabalah, which means the "science of restoration and balancing."
I solved equations using both algebraic methods of solution and geometric methods of solution...in fact the term "completing the square" can be traced to my efforts.
The word "algorithm" is derived from my name.
Mohammed ibn-Musa al-Khowarizmi, c. 780-850