Notes

Notes are individual pitches and as such represent the smallest indivisible elements of music. The term applies both to pitches as they sound on an actual musical instrument, as well as to the symbols used to represent the notes in musical notation.

Notes are combined in various ways to form chords and scales, which are the principles behind the fundaments of music: melody and harmony.

Note Names

Natural Notes

Western music uses 12 notes. Of these notes, seven have their own distinct names and are referred to as natural notes. The names we use for them are C, D, E, F, G, A and B:

The natural notes correspond to the white keys of a typical piano keyboard:

Enharmonic Notes

The other five notes, corresponding to the black keys, are collectively referred to as enharmonic notes. This means that they sound the same but are written differently. As you see, there is only one key between for instance C and D, but this note can either be considered as related to C, or related to the note on the other side—D:

C#
Db

D#
Eb

F#
Gb

G#
Ab

A#
Bb

To indicate that a natural note has been raised or lowered by a half-step, a sharp (#) or flat (b) sign is added to the note:

For example, the note between C and D can be referred to either as C sharp (C#, for short) or D flat (Db).

Since any natural note can be assigned a sharp or flat sign, even some of the natural notes have enharmonic equivalents:

C#
Db

D#
Eb

F#
Gb

G#
Ab

A#
Bb

B#
C

Fb
E

E#
F

Cb
B

Double Sharps and Flats

Notes can also be raised or lowered by two half-steps. The double-sharp sign is similar to a lower-case X, the double-flat sign looks exactly the way the term sounds:

In the same fashion, a C can also be rewritten as a D double-flat (Dbb), whereas a D might occur as a C double-sharp (Cx).

When double flats and sharps are used, most notes—natural or enharmonic—have two enharmonically equivalent notes:

Bx
C#
Db

Fbb
D#
Eb

Ex
F#
Gb

G#
Ab

Cbb
A#
Bb

Dbb
B#
C

Cx
Ebb
D

Dx
Fb
E

Gbb
E#
F

Fx
Abb
G

Gx
Bbb
A

Ax
Cb
B

If you count them, you will see that there are 35 note names in total. It all adds up, because there are seven natural notes and four kinds of accidentals per note—five if the natural note is also counted. 7 times 5 = 35.

The reason why we have this many names for comparatively few notes is that Western music theory and notation have evolved throughout the years to fit a system with seven-note scales. With the 12 key centers that are possible with the 12 notes, you will eventually need some extra note names to keep your notation tidy.

Pitch Notation

An interesting property of music is that two notes whose frequency are at a 1:2 ratio are very similar. Indeed they are the same notes, but in different registers. The 1:2 frequency relationship is called an octave, because in the system of seven-note scales, the eighth note is where the scale restarts.

(Please see the separate articles about intervals and overtones for more information about the octave and the 1:2 relationship.)

The illustration above shows that the 12 notes recur, from the lowest of lows to the very top of the register. Most of the time in music theory, the exact pitch or register of a note is irrelevant, and thus theorists tend to talk about pitch classes, which basically means any C, D, F, A flat or whatever, irrespective of its register.

In the contexts where register is important, there is a way to distinguish the seven or eight octaves that are used in most music. English-language music theory normally uses scientific pitch notation, where the lowest C on a grand piano is C1 and the notes below that C are termed A0, Bb0 etc.:

Abbreviation & range	Name
C0-B0
C1-B1	Double-pedal
C2-B2	Pedal
C3-B3	Bass
C4-B4	Middle
C5-B5	Treble
C6-B6	Top
C7-B7	Double-top
C8-B8	Triple-top

This is relevant, because international standard has fixed the pitch of middle A to a frequency of 440 Hertz. And as we will soon see in the article on musical notation, the relative pitches of notes on the staff are fixed by adding clefs that pinpoint the position of middle G, middle C or bass F.