In the Hindu-Arabic system, the second stage of number representation was attained. Here the big idea is to make the value of a symbol dependent upon where it occurs in the string. This allows us to express any number withjust a fixed family of symbols. We have settled on the set of ten numerals 0,1,2,…,9,so the normal number system is described as base ten, but we could build our number system up from a larger or a smaller collection of basic symbols. We can even manage with as few as two numerals,0 and 1 say, which is what is known as the binary system, so of ten used in computing. It is not the choice of base size, however, that was revolutionary but the idea of using position to convey extra information about the identity of your numbers.