Natural Minor Scale

The musical scale that differs from the major scale in that three of the tones are flatted a half-step. It is identical to the Aeolian mode of the major scale.
For example:

• A Natural Minor contains the notes: A B C D E F G
• F# Natural Minor contains the notes: F# G# A B C# D E
• D Natural Minor contains the notes: D E F G A Bb C

Based on the intervals between the notes, the standard triads used when playing a piece in a minor scale follow the pattern:
minor, diminished, major, minor, minor, major, major.

Specifically, if you were to looking at a classical piece in A minor, the chords would (probably) be as follows:

 i   ii0   III  iv  v    VI    VII
Am  Bdim    C   Dm  Em    F     G
Am7 Bm7b5 Cmaj7 Dm7 Em7 Fmaj7 Gmaj7

Not a very exciting scale. I know a guy who's vehemently opposed to using the sixth tone of the scale when playing it, because it makes it sound very slightly like you're playing the relative major scale. I find it most interesting to throw in extra notes, in order to jump back an forth between natural minor and the harmonic minor scale, and/or the minor blues scale.

The relative minor scale contains seven modes. They are, from the first up (in the key of A Minor):

• Aeolian (I) — A B C D E F G A (same as the minor)
• Locrian (II) — B C D E F G A B
• Ionian (III) — C D E F G A B C
• Dorian (IV) — D E F G A B C D
• Phrygian (V) — E F G A B C D E
• Lydian (VI) — F G A B C D E F (same as the relative major)
• Mixolydian (VII) — G A B C D E F G

The guitar pattern for the scale is:

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The bass pattern for the scale is:

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The piano pattern for the scale is:

A  B  C  D  E  F  G  A
1  2  3  1  2  3  4  5

Source: The Keyboard Grimoire (book), Advanced Scale Concepts and Licks for Guitar (book)