Who Invented Arabic Numerals?
It should be noted that the Arabic numerals were neither invented by nor used by the Arabs. They were developed in India by the Hindus around 600 A.D. Interestingly, these numbers were written "backwards", thus one hundred twenty three was written 321.
Around 750 A.D. this system of decimal arithmetic was brought to Persia when several important Hindu works were translated into Arabic. The noted Arab mathematician al-Khwârizmî (Muhammad b. Musa al-Khwârizmî ca. 875) wrote a textbook on the subject which now exists only in a number of Latin versions. In these a point is used for zero.
In ca. 952 Abu'l-Hasan-al-Uqlidisi wrote the Book of the Parts of Indian Arithmetic which contains an explanation and application of decimal fractions. In the transmission of Arabic numerals to Europe the method of writing numbers became reversed to the present method in the process.