I made this post over in acoustic talk (not realizing there was a board basically for theory) and I got a suggestion to try it here.

I was thinking of posting a quick tutorial of modes on a article that mentioned them but didn't explain them, but then I thought better of myself as I'm not rock solid in the area. I figured I'd post what I came up with here and get some corrections and critiquing of my own understanding. This isn't supposed to be a guide that I trying to get people to use, I'm just looking for a check on my own understanding-although if it is right and it helps someone that's cool too.

Most descriptions of modes are fairly reliant on knowledge of a Major Scale. The Major Scale is simply a set of 8 notes with a specific interval between each note. The order of these intervals is w-w-h-w-w-w-h, with "w" being a whole step, and "h" being a half step. A C Major scale contains no flats or sharps because there is a whole step between each natural note except for B-C and E-F, which have half steps. These notes happen to be located at the 7th-8th scale degrees and 3rd-4th scale degrees, respectively, resulting in a scale with no flats or sharps.

Modes can basically be thought of as augmenting an Major scale or starting an alternate Major scale from a different scale degree, based on the name of the mode. Running a D Dorian scale is basically playing a C Major scale going from D to D instead of C to C. Alternatively you can memorize the differences in all the modes alternatively. D Dorian is a D Major scale with a flat 3rd and 7th degree (in this case, F and C). An interesting example is the Aeolian mode which is also known as a natural minor scale-both having a flat 3, 6, and 7 degree. You could think of playing this mode/scale this way, or by thinking of it as playing a C major scale starting from A since A is the 6th degree of the C scale.

An important note is that D Dorian, E Phrygian, etc are all diatonic to C Ionian, or Major, but only because they happen to be the second and third degrees of the C Ionian mode. E Dorian, for example, can be thought of as playing an E Major scale with a flat 3 and 7, or as playing an 8 note scale in the key of D Major starting from E, the second degree.

Degree started from: (think of the mode name as this scale degree of a Major Scale)

Ionian-1
Dorian-2
Phrygian-3
Lydian-4
Mixolydian-5
Aeolian-6
Locrian-7

Augmentations to Major Scale: (think of a Major Scale of the mode's name, but with these augmentations)

Ionian-Major
Dorian-flat 3, 7
Phrygian-flat 2, 3, 6, 7
Lydian-sharp 4
Mixolydian-flat 7
Aeolian-flat 3, 6, 7 (also Natural Minor)
Locrian-flat 2, 3, 5, 6, 7
>.> modes are always an argument here and there is a sticky for them..............

there even in the fact aswell which is also stickied....