Modal theory is something that helps us understand how scales work. It helps us understand the relationship between scales and how they work together as one to achieve the goal. The reason they are called "modes" is they are not actually completely different scales, but rather different "modes" of the same scale. If this is confusing, do not be concerned, just read on and it will be explained.

To start, the names of the modes must be learned and memorized. I know, memorizing things is not everyone's favorite thing to do and I do try to keep those things to a minimum, but this is essential and must be memorized.

We will start with the major scale, which is also called "IONIAN". This will be the first mode we learn. The ionian mode (or major scale) is a seven note scale, and therefore has seven modes. The names of these seven modes MUST be memorized and they must be memorized IN ORDER.

They are (in order) :

1. Ionian    (i-o-nee-in)
2. Dorian    (door-e-in)
3. Phrygian    (fridge-e-in)
4. Lydian    (lid-e-in)
5. Mixolydian    (mix-o-lid-e-in)
6. Aeolian    (a-o-lee-in)
7. Locrian    (lo-cree-in)

It helps to just say them over and over to yourself until you remember them. Don't forget that they have to be remembered in the proper order. Once you have these seven mode names memorized in the proper order then you can move on to the "key construction" lesson.

Also, I highly recommend this book as an excellent guide to every scale you ever wanted to know.