
The key signature is a list of all the sharps and flats in the key that the music is in. The clef tells you the letter name of the note (A, B, C, etc.), and the key tells you whether the note is sharp, flat or natural. They appear so often because they are such important symbols they tell you what note is on each line and space of the staff.

In common notation, clef and key signature are the only symbols that must appear on every staff. If there are no flats or sharps listed after the clef symbol, then the key signature is “all notes are natural”. It may have either some sharp symbols on particular lines or spaces, or some flat symbols, again on particular lines or spaces. The key signature comes right after the clef symbol on the staff. Key signatures are generally written immediately after the clef at the beginning of a line of musical notation, although they can appear in other parts of a score, notably after a double bar.


Exceptions Created by Harmonic Sequences.Shorter Progressions from the Circle of Fifths.9 Harmonic Progression and Harmonic Function.Roman Numerals of Diatonic Seventh Chords.How to Write Perfect, Major, and Minor Intervals.How to Identify Perfect, Major, and Minor Intervals.
