The Arabic Numerals

بِسۡمِ ٱللهِ ٱلرَّحۡمَـٰنِ ٱلرَّحِيمِ

The Arabic numerals we us were created by Imam Muhammad ibn Musa al-Khwarizmi (r.a.), a Persian scholar of the natural sciences, and mathematics.  These numbers were based on the number of angles in the digit, as can be seen here.  As part of the decimal system, they are the foundations of our modern society. 

Imam al-Khwarizmi (r.a.) was appointed the chief astronomer in the House of Wisdom, in Baghdad.  We are indebted to his contributions to navigation, from inventing much of the mathematics we use, to writing extensively on cartography, celestial movements, and calculating the size of the Earth, and distances between cities.  His work also allowed for a more accurate calendar, which became more important, as civilisation advanced.