Numeration systems are ways of counting and of naming numbers. They are also called numeral systems. We cannot see or touch numbers, because they are ideas. But we can use symbols to stand for numbers. These symbols are called numerals. Here are three numerals that represent the number in a half dozen: 6, six, and VI.
The most commonly used numeration system has 10 basic numerals, called digits: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9. With these 10 symbols we can represent any number. This system is called a decimal system because it is based on 10. The word decimal comes from the Latin word for ten. Ten is the base or the scale of the decimal system.
