The Highest Common Factor (HCF) of 7 and 8 is 1. The HCF, also known as the Greatest Common Divisor (GCD) or the Greatest Common Factor (GCF), is the largest number that can divide two or more numbers without leaving a remainder. In the case of 7 and 8, the HCF is 1. For a more detailed explanation, you can visit the Highest Common Factor page.