Essential Music Theory How to read music
At the beginning of each piece of music there is a time signature. The time signature tells us how many beats will be in each of the bars that follow the time signature. If there are a different number of beats in any subsequent bars then a new time signature is written before that bar to show the change of time signature.
When music has four beats in the bar the time signature is either shown as a 'C' to denote common time (Figure 13) or '4/4' (Figure 14).
Figure 12. Common time (Enlarge)
Figure 13. Four four time. (Enlarge)
Next: Reading time signatures