When did the Arabic numeral system develop?
Hindu–Arabic numeral system
It was invented between the 1st and 4th centuries by Indian mathematicians. The system was adopted in Arabic mathematics by the 9th century. Influential were the books of Muḥammad ibn Mūsā al-Khwārizmī[3] (On the Calculation with Hindu Numerals, c.825) and Al-Kindi (On the Use of the Hindu Numerals, c.830). The system later spread to medieval Europe by the High Middle Ages.
History of ancient numeral systems
Numeral systems have progressed from the use of tally marks, more than 40,000 years ago, through to the use of sets of glyphs to efficiently represent any conceivable number.