Prime factorization is the process of breaking down a number into its prime factors.
Ok, let's break that statement down:
How to Do It
Here's a nice way to visualize factors: a factor tree. Start by finding any factor of the number at top. Circle the factor if it's a prime number. That branch ends right there. Otherwise, keep factoring each branch down until all of the branches end in circles (that is, prime numbers).
You can check your answer by multiplying all the prime factors together.