- A factorial of a number is the product of all positive integers from 1 up to the number.
- The only exception is 0, where its factorial is 1.

Take, for example, How it would calculate the factorial of
`4`

.

`4 * 3 * 2 * 1 === 24;`

`public class main { static int factorial(int n) { if (n == 1) return 1; else return (n * factorial(n - 1)); } public static void main(String[] args) { System.out.println("Factorial of 8 is: " + factorial(8)); } }`

`Factorial of 8 is: 40320`