A divisor is a number that can divide another number without leaving a remainder. For example, in the case of the number 12, its divisors include 1, 2, 3, 4, 6, and 12. This means that when you divide 12 by any of these numbers, the result is a whole number. Divisors are important in various areas of mathematics, including number theory and fractions. They help in simplifying fractions and finding common factors. Understanding divisors can also assist in solving problems related to multiples and greatest common divisors (GCD).