A human hand carries five fingers; two hands have ten of them. Undoubtedly, this fact is responsible for the universal adoption of the decimal system.
Children learn to count by counting fingers, first to 5 on one hand and then to 10 on two hands. However, there is a simple way to count to 10 with just 5 fingers of one hand and to 100 using both hands.
This is how:
A folded fist may stand for 10 if you do not plan to use the second hand, or for 0 if you do:
The second hand is used in the same manner but for counting 10s:
|twenty six||fifty five|
(There is an interesting discussion on the web concerning finger counting.)