Muhammad ibn Musa al-Khwarizmi (c. 780 - 850 A.D.)

• persian scholar from golden-age of islamic science
• his name Latinized as "Algorithmi" (Port. "guarismo" and Spanish "algarismo" mean digit)
• since 820 A.D. the astronomer and head of the House of Wisdom in Baghdad
• contributions to Algebra, Arithmetic, Astronomy, Trigonometry, Geography