Bar lines divide the musical staff into equal "measures" of time.

Below is a song Twinkle, Twinkle Little Star with quarter notes, half notes and 
the bar lines added. Did you recognize this song from the last lesson?

Notice that each bar line comes after 4 counts. (beats)
In this song, we therefore have 4 beats per measure. 
If we count all the measures, we find we have a total of 12.
All music is usually divided into equal "measures" of time.
We also have a bar line at the beginning and end of each staff.

Also notice that we have a different kind of bar line at the end of the last measure of the song. This is called a double bar line.

When you see a double bar line, it means you the song ends at that point.

		Click on the play button again and play along with Twinkle, Twinkle Little Star. This time the bar lines have been added. If you can't see the music below, not to worry. This means you need to download the free scorch music plug-in.