The Time Signature is a set of 2 numbers stacked on top of each other at the beginning of just about every piece of music. The time signature tells us what the beat of the music is. If the beat of the music changes during the song, you will sometimes see a time signature in the middle of a song. Most songs keep the same beat for the whole time, so you will usually only see the time signature at the beginning.
The top number of the time signature tells us how many beats are in each measure (or bar) of the music. When we are counting rhythms, this will be the number we are counting to. So if the top number is 4, we will be counting to 4 because there are 4 beats in each bar. If the top number is a 3, we will be counting to 3. If the top number is a 7, we would count to 7.
The bottom number of the time signature tells us which kind of note gets one beat. This is the note that we will be counting when we are counting rhythms. If the bottom number is a 4, we will be counting quarter notes. If the bottom number is a 8, we would count 8th notes. Sometimes you will see a 2 or a 16 on the bottom. This means we would be counting either half or sixteenth notes.
The time signature that we will see most often is 4/4. In fact, another name for 4/4 time is "Common Time". In some older music, instead of a "4/4" at the beginning of the music, you will see a "C". This means the same thing as 4/4.
"The first verse is twelve measures long but with varying measure lengths which appear as follows: 3/4, 4/4, 3/4, 3/4, 5/4, 4/4, 5/4, 4/4, 3/4, 3/4, 4/4 and 4/4. (This, however, is left to interpretation and may vary in sheet music or personal opinion.)"
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