Al-Khwarizmi and the Birth of a Word

Muhammad ibn Musa al-Khwarizmi, a 9th-century Persian scholar working in Baghdad's House of Wisdom, wrote a treatise on systematic methods for solving equations.

His name, Latinized centuries later as "algorithmi," became attached to the step-by-step methods he described — and eventually to the general concept itself.

(His other book's title gave us a second word: al-jabr — "algebra.")