Article 1. A Unit is a single thing. 2. A Number is a unit or collection of units. 3. In counting a large number of objects it is natural to group them. Thus, coins are put in piles and the piles counted, envelopes in packages and the packages counted, etc. These piles and packages may themselves be piled and put in larger packages, and the process continued indefinitely. 4. To express numbers so that all may understand what is meant by the characters which represent them, the system of grouping by tens has been adopted. There are, therefore, single things, or units; groups of ten units, or tens; groups containing ten tens, or hundreds, etc. 5. The method of grouping by tens is called the Decimal System. Decimal is derived from the Latin word decem, which means ten. |