Definition:Decimal Notation

Definition
Decimal notation is the quotidian technique of expressing numbers in base $10$.

Every number $x \in \R$ is expressed in the form:
 * $\displaystyle x = \sum_{j \mathop \in \Z} r_j 10^j$

where:
 * $\forall j \in \Z: r_j \in \left\{ {0, 1, \ldots, 9}\right\}$

Also see

 * Decimal Expansion