Today we will learn about time signature. It is a notation used in Western music and it shows how many beats are contained in a bar, and also which note value will be set to a beat. This is a way to ‘organize’ a song so that it will be easier to play and listen.
There are two types of time signature: simple and compound. In this lesson, we will learn about simple time signatures.
The time signature appears always at the beginning of a music piece, just after the key signature, as shown in the example below:

It’s possible to change the time signature in a song. In this case, we need to show it in the score. We do that by writing the new time signature in the beginning of a barline:

The example above shows that there are 4 bars in 4/4 and then from the 5th bar on the time signature has changed to 3/4.
If we want to change the time signature back to 4/4, we need to indicate that in the score:

In the example above, there are 2 bars in 4/4, then 2 bars in 3/4 and then from the 5th bar on the song changes again to 4/4.
In short, if the time signature will never change, we just need to put it in the beginning of the score.

The numbers of a simple time signature have specific meanings. The top number will tell us how many beats a bar will have. So, 4/4 means that the bar will have 4 beats. We play it by counting one-two-three-four. Likewise, a 3/4 time signature means that each bar will have 3 beats. In simple time signatures, the top number will always be 2,3,4,5 or 7.
The bottom number is the note value of each beat. Each note value will have a number to represent it, as shown in the table below:


So, a 4/4 bar (we read four-four time) means that each bar will have four beats and each beat will have the value of a quarter note.

Notice that the total of beats of a 4/4 bar is 4, the equivalent to a whole note.
Similarly, a 2/4 time signature will have two beats, and each beat will have the value of a half note.
Most composers of popular music genres, such as rock, pop, hip-hop and rap usually write their songs in a 4/4 time signature.
That makes a little trickier to understand and play other simple time signatures, like 3/8 and 2/2. We are so familiar with 4/4 beats that we find difficult to follow a 5/4 or even a 7/8 beat.
But that’s the subject of our next lesson.
Good productions!