Although a system such as the Roman numeral system is adequate for recording the results of counting, it is too cumbersome for purposes of calculation. The idea of 0 as a number. Positional notation is a form of coding in which the value of each digit of a number depends upon its position in relation to the other digits of the number. The convention used in our number system is that each digit has a higher place value than those digits to the right of it. The place value which corresponds to a given position in a number is determined by the BASE of the number system.
Any number is assumed to be a base-ten number, unless some other base is indicated.
One exception to this rule occurs when the subject of an entire discussion is some base other than ten. In the decimal system, each digit position in a number has ten times the value of the position adjacent to it on the right. Since ten plus one is eleven, the symbol 11 represents the number eleven. Figure l-l shows the names of several digit positions in the decimal system. Some of these groups are shown in table l-l.