Beats
A measure is generally divided into two, three or four subdivisions called beats. Thus, there are 2 beat, 3 beat and 4 beat measures.
When the number of beats in a measure are divisible by two, the rhythm is referred to as "binary" and constitutes "simple" meter.
When the number of beats in a measure are divisible by three, the rhythm is referred to as "ternary" and constitutes "compound" meter.