Footnotes on 2.3

Remember that long division and remainders are discussed in Section 2.3. For every two numbers n and m, there are numbers q (for quotient) and r (for remainder) such that m=nq+r and 0 ≤ r ≤ n-1.

We say that a natural number A divides a natural number B

We also say that A is a divisor of B, and B can be divided by A, or B is a multiple of A. For example, 2 divides 4 but 2 does not divide 5.