Editing Greatest common divisor (section)

=== Example ===

The number 54 can be expressed as a product of two integers in several different ways:
: <math> 54 \times 1 = 27 \times 2 = 18 \times 3 = 9 \times 6.</math>

Thus the complete list of ''divisors'' of 54 is 1, 2, 3, 6, 9, 18, 27, 54.
Similarly, the divisors of 24 are 1, 2, 3, 4, 6, 8, 12, 24.
The numbers that these two lists have ''in common'' are the ''common divisors'' of 54 and 24, that is,
: <math> 1, 2, 3, 6. </math>

Of these, the greatest is 6, so it is the ''greatest common divisor'':
: <math> \gcd(54,24) = 6. </math>

Computing all divisors of the two numbers in this way is usually not efficient, especially for large numbers that have many divisors. Much more efficient methods are described in ''{{slink|#Calculation}}''.