In modern usage, this latter symbol is usually a vinculum (a horizontal line placed over the repeating digits). In a more developed form, positional notation also uses a decimal marker (at first a mark over the ones digit but now more commonly a decimal point or a decimal comma which separates the ones place from the tenths place), and also a symbol for 'these digits recur ad infinitum'.

The Hindu–Arabic system is designed for positional notation in a decimal system. Main articles: Positional notation and 0 (number) According to some sources, this number system may have originated in Chinese Shang numerals (1200 BC), which was also a decimal positional numeral system. Later they came to be called 'Arabic numerals' in Europe because they were introduced to the West by Arab merchants. Persian and Arabic mathematicians called them 'Hindu numerals'. The Hindu–Arabic numerals were invented by mathematicians in India. These symbol sets can be divided into three main families: Western Arabic numerals used in the Greater Maghreb and in Europe Eastern Arabic numerals used in the Middle East and the Indian numerals in various scripts used in the Indian subcontinent. The glyphs in actual use are descended from Brahmi numerals and have split into various typographical variants since the Middle Ages. The symbols (glyphs) used to represent the system are in principle independent of the system itself.

The system is based upon ten glyphs representing the numbers from zero to nine, and allows representing any natural number by a unique sequence of these glyphs. The system had spread to medieval Europe by the High Middle Ages. 825) and Arab mathematician Al-Kindi ( On the Use of the Hindu Numerals, c. It became more widely known through the writings in Arabic of the Persian mathematician Al-Khwārizmī ( On the Calculation with Hindu Numerals, c. The system was adopted in Arabic mathematics by the 9th century. The Hindu–Arabic numeral system was invented between the 1st and 4th centuries by Indian mathematicians. The Hindu–Arabic numeral system or Indo-Arabic numeral system (also called the Hindu numeral system or Arabic numeral system) is a positional base ten numeral system for representing integers its extension to non-integers is the decimal numeral system, which is presently the most common numeral system.

Modern-day Arab telephone keypad with two forms of Arabic numerals: Western Arabic numerals on the left and Eastern Arabic numerals on the right

Concept ancient glyphs