From the Series: A'lam al-Fikr al-Arabi (Notables of Arab Thought): The polymath of the Abassid era, Al-Khwarizmi (ca. 780 - ca. 850 AD).

«Khwarizmi produced vastly influential Arabic-language works in mathematics, astronomy, and geography. He has been described as the father or founder of algebra. The English term algebra comes from the short-hand title of his aforementioned treatise (الجبر Al-Jabr, transl. 'completion' or 'rejoining'). His name gave rise to the English terms algorism and algorithm; the Spanish, Italian, and Portuguese terms algoritmo; and the Spanish term guarismo and Portuguese term algarismo, both meaning 'digit'.»(Wiki)