Because its sound is so familiar the major scale has been used for centuries as the standard musical reference scale. The characteristic sound of the major scale (or any other scale) is created by its structure (order of whole and half steps), which is the same in all keys. In the Universal Key system the tones of the major scale are expressed as numbers: DO = 1, RE = 2, MI = 3, FA = 4, SO = 5, LA = 6, TI = 7, DO = 1 (8). Non-major tones are expressed in terms of their relationship to the major scale (Eb in the key of C is b3. Ab in the key of D is b5). Chord tones which are second octave extensions of seventh chords are listed in parentheses (9, #11, etc.). The note of any chord or scale may be found in any key by comparing the formula for any chord or scale from the CHORD AND SCALE TABLE (or other reference source) to the TABLE OF KEYS.

Example:
This example shows how one scale (G major) relates to the Universal Key, the piano keyboard, and the treble staff.

Every key signature describes a major key (capital letters) and its relative minor key (small letter). These scales have the same notes but befin on different tonics. In a key signature sharps and flats name, by the line or space on which they fall, the notes of the C major scale which must be altered to play in the designated key.

The notes of any chord or scale may be found in any key by comparing the formula for any chord or scale from the CHORD AND SCALE TABLE to the TABLE OF KEYS.
To find the notes of any chord: Example: Fm7
1. Use the CHORD AND SCALE TABLE (or other reference source) to find the chord formula (minor seventh = 1 b3 5 b7).
2. Look on the TABLE OF KEYS for the key (key of F).
3. Find the notes in that key that correspond to the numbers of the chord formula (1 = F, b3 = Ab, 5 = C, b7 = Eb).

Roman numerals (I,IV, V, etc.) are used to indicate major chords built off any scale degree. Other chords (minor, seventh, etc.) are represented by a Roman numeral followed by the abbreviation for that chord type (IVm would be a minor chord with the fourth degree of the major scale as its root). The Roman numeral system is used extensively by working musicians for writing chord charts.
Example: Transpose this progression from the key of C to the key of F.

1. Find the letter names of all the chord types in the original progression (C, G, A, and D).
2. Find the numerals fo the Universal Key that correspond to each chord (C = 1,G = V, A = VI, and D = II), then add the chord type suffix (m, 7, dim, etc.). Written in the Universal Key, the progression would be I / V7 / I / I / VIm / II7 / V7 /I. (Variation: sometimes lower case Roman numeral are used to indicate minor chords [ex., vi instead of IVm]).
3. Find the chord of the new key that corresponds to the numerals of the progression. (I = F, V = C, VI = D, II = G).
4. Write out the progression in the new key, adding the appropriate chord types.
Progression in the key of F: F / C7 / F / F / Dm / G7 / C7 / F

The lines and spaces of the Great Staff take their names from the notes of the C major scale which fall on them. Notes which are outside the C major scale are designated by accidentals: sharps(#) raise notes one half step; flats(b) lower the notes one half step; double sharps(x) raise notes a whole step; double flats(bb) lower notes a whole step; naturals() cancel the effect of other accidentals.