arabic numbers

All Arabic numbers we use today are ideograms created by Abu Ja'far Muhammad ibn Musa al-Khwarizmi (c.778 - c.850).Al-Khwarizmi was born in Central Asia, where today is placed the Uzbekistan, and then he moved to Baghdad, where he worked as a mathematician during the first golden age of Islamic Science, at the "House of Wisdom".
Using the abacus notations, he developed the manuscript decimal system.Based on additive angles, he defined the numbers 1, 2, 3 and 4.And using his knowledge about the abacus manuscript notations, he defined the numbers 5, 6, 7, 8, 9, O.