Currently we use numbers that appeared in India. Once they had the appearance of the initial letters of the corresponding words in the ancient Indian language of Sanskrit alphabet "Devanagari").
The most important step in the development of digital systems was the introduction of a special mark of our prototype zero. He was a fat dot or circle. This allowed a smaller number of characters. Numbering "Devanagari" turned into a decimal local system. How and when this happened is unknown. But already in the VIII century the system has been infiltrated in other countries: Indochina, China, Tibet, Iran, Central Asia. In the early ninth century Mohammed from Khorezm spread Indian numbering in the Arab countries.
In Europe these figures were in the XII century and the sixteenth century, thanks to its versatility, totally established. As to the Europeans, the system "Devanagari" came from the Arabs, they called it the "Arab". This is historically incorrect name persists to this day.