Born into a Persian family in Khuwarizm (present-day Xorazm Province, Uzbekistan), Muhammad ibn Musa al-Khwarizmi (also known by the Latin form of his name, Algoritmi, circa 780--850 AD, 164--236 AH) was a Muslim mathematician, astronomer, and geographer, and a scholar in the famed House of Wisdom in Baghdad. Al-Khwarazmi wrote Kitab al-Jabr wa-l-Muqabala (The compendious book on calculation by completion and balancing) around 830 AD, with the encouragement of Caliph Al-Maamoun, the reigning Abbasid caliph of Baghdad in 813--33 AD. It is meant to be a useful work, with examples and applications for everyday life, in areas such as trade, legal inheritance, and surveying. The mathematical term algebra is derived from al-jabr, one of the two operations he used to solve quadratic equations. Also, the words algorism, algorithm, and arithmetic stem from Algoritmi. Similarly, his name is the origin of the Spanish term guarismo and of the Portuguese algarismo, both meaning digit.