Definition:Congruence (Number Theory)/Integers/Integer Multiple

Definition
Let $m \in \Z_{> 0}$. Let $x, y \in \Z$.

Then $x$ is congruent to $y$ modulo $m$ iff their difference is an integral multiple of $m$:
 * $x \equiv y \pmod m \iff \exists k \in \Z: x - y = k m$

Also see

 * Equivalence of Congruence Definitions


 * Congruence Modulo $m$ is Equivalence Relation