An object, a figure and a unit of measurement can all be regarded as the unit "1". Divide the unit "1" into several parts on average, and the number representing such a part or parts is called a fraction. In the music,

The denominator indicates how many parts the unit "1" is divided into, and the numerator indicates how many parts there are; One of them is called fractional unit.

Fraction indicates the fraction of one number to another, or the ratio of one event to all events. Divide the unit "1" into several parts on average, and the number representing such a part or parts is called a fraction. The numerator is above and the denominator is below.