There are three types of pulses
And two types of counting
Simple meters are those in which the note on the bottom of the time signature gets the beat. The beats are divisible by two (if the quarter note gets a beat, it can be divided into two eighth notes)
Compound Meters are when the beat is divided by three. (I.E. a dotted half note gets the beat, this can be divided into three quarter notes).
A simple way to tell the difference:
If the top number is a 6, 9, or 12 it is COMPOUND meter.
6/8 is an example of compound meter. The sixth eigth notes are grouped into two groups of three eihth notes each. So the big beat is the dotted quarter note (three eighth notes tied together).
So you can see that a meter may be