In this tutorial the author shows how to factor a number. He says that factoring means to find all the smaller numbers which can be multiplied to obtain the original number. He says that the number one and the number it self are the factors of every number. Now to find the factor of a number he starts with 2 and tries to divide that number with 2. If he is able to divide it, it implies that 2 is a factor of that number. He now does this with each and every number between 1 and the number it self to find all the factors of a given number. This video gives a good introduction on how to find factors of any number.