Part of our section on Musical Notation where we look at the elements of a music score.
This page follows on from our page on middle C.
The # symbol immediately following the treble clef sign is called a sharp. It is on the top line of the music stave which means it is an F# (F sharp)..
We call this the key signature and it means that every F note that follows should be played as F# (the black note above F on a keyboard).
This is the key signature of the G major music scale
The key signature can contain a number of # (sharp) symbols or one or more ♭ (flat) symbols depending on the music scale.
The scales of C major and A minor have no sharps or flats in their key signatures.
Every other major and minor scale has one or more sharps or one or more flats.
Note that a key signature is never a mix of sharps and flats.
The key signature is usually repeated at the start of each line of a music score.
The key signature can change from one scale to another in the middle of a music score. This is called modulation.
For other examples of key signatures see our pages on on Major scales and Minor scales
Continue to explore musical notation on our page on Time signatures
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