Numerator

The numerator is the top part of a fraction.
For example, in the fraction 3/4, the numerator is 3.

3 <==== numerator
4

The number on the bottom is called the denominator. This is the number of parts out of the total number of parts that your fraction has. For example, if you cut a pizza into 4 pieces, and you get 3 (the numerator), then you got 3/4 of the pizza.

Now, here's a question for you:
In the fraction 5/8, what is the numerator?