The Indian numerals discussed in our article Indian numerals form the basis of the European number systems which are now widely used. However they were not transmitted directly from India to Europe but rather came first to the Arabic/Islamic peoples and from them to Europe.
There are other complications in the story, however, for it was not simply that the Arabs took over the Indian number system. Rather different number systems were used simultaneously in the Arabic world over a long period of time.
For example there were at least three different types of arithmetic used in Arab countries in the eleventh century:
A system derived from counting on the fingers with the numerals written entirely in words, this finger-reckoning arithmetic was the system used for by the business community;
- The sexagesimal system with numerals denoted by letters of the Arabic alphabet;
- The arithmetic of the Indian numerals and fractions with the decimal place-value system.
Partial Source: http://www-history.mcs.st-andrews.ac.uk/Projects/Pearce/index.html