Key Signatures
Instead of writing a sharp sign before every F note on the staff, it is easier to write just one sharp sign after each clef. This means that all the F notes on the staff are played as F# , even though there is no sharp sign written before them. This is called a key signature.
The G Major Key Signature
This is the key signature for the key of G major. It has one sharp sign after each clef.
The C Major Key Signature
The C major scale contains no sharps or flats, therefore the key signature for the key of C major contains no sharps or flats.
I Yi Yi Yi is in the key of G major. Notice the key signature and play all F notes as F#. This is one of the most well known songs from Mexico. The left hand accompaniment contains chords played staccato in the first part of the song and broken chords in the second half.
Also notice that bar 10 contains a whole rest, which would typically indicate four quarter note rests, but this can also be used for a full bar of rest. As this piece is in 3/4 time, it represents a full-bar rest (in this case, three quarter note rests).
