GCF is also known as the ‘Greatest Common Factor’. It is the largest or greatest number among all the common factors of the given numbers. It is referred using different names. Such as: HCD ( Highest Common Divisor ), HCF ( Highest Common Factor ), GCD ( Greatest Common Divisor). They are often used all the time with fractions. We can find the GCF of the numbers using three different methods. They are: prime factorization, division method, and listing out common factors.