Prehistoric counting
Counting in prehistory was first assisted by using body parts, primarily the fingers. This is reflected in the etymology of certain number names, such as in the names of "ten" and "hundred" in the Proto-Indo-European numerals, both containing the root *"dḱ" also seen in the word for "finger" (Latin "digitus", cognate to English "toe"). Early systems of counting using tally marks appear in the Upper Paleolithic. The first more complex systems develop in the Ancient Near East together with the development of early writing out of proto-writing systems. Background. Numerals originally developed from the use  of tally marks as a counting aid, with the oldest examples being about 35,000 to 25,000 years old. Development. Counting aids like tally marks become more sophisticated in the Near Eastern Neolithic, developing into numerical digits in various types of proto-writing during the Chalcolithic. Early numerals in Unicode. Unicode's Supplementary Multilingual Plane has a number of code point ranges reserved for prehistoric or early historic numerals: