Composite numbers are numbers we get by multiplying together other numbers. Some numbers, however, have no factors other than themselves and one. Such numbers are called prime , and there are infinitely many of these.
Every natural number is either prime or can be uniquely factored as a product of primes.
Let's look at an example. One way of interpreting the FTA is to say that the prime numbers are the building blocks, so to speak the bones, out of which the set of natural numbers is built. In this theory, many beautiful things about the natural numbers are proved. Please send comments or corrections to PRME comments .