A composite number is a positive integer that has more than two factors. In other words, it is a number that can be formed by multiplying two smaller positive integers. For example, 6 is a composite number because it can be formed by multiplying 2 and 3. On the other hand, prime numbers are numbers that have only two factors, 1 and the number itself. All even numbers except 2 are composite numbers. The smallest composite number is 4. The numbers 0 and 1 are neither prime nor composite numbers. Every composite number can be written as the product of two or more primes, and this representation is unique up to the order of the factors. This fact is called the fundamental theorem of arithmetic.