From the latin word modus which means "measure, standard, way" it generally and simply refers to a type of scale. It is interesting to note that the beginning note of a modal scale is called the final rather than the tonic as in other diatonic scales.

Modes I, III, V and VII are called authentic because the final is at the bottom of the range. Modes II, IV, VI and VIII are called plagal because they have the same whole and half steps as the authentic but their range sorrounds the final.









Before proceeding any further, for the benefit of those who are totally at a lost regarding modal scales, what are they and how exactly are they constructed. Take a look at the image below.




Look at this image and the given modal scale names. Let me elaborate a little more as to how they are constructed. Let us take into account the C major scale. The Ionian mode is exactly the same with the major scale. So, if you are in the key of C, the Ionian mode is simply C D E F G A B C. 


Let us now discuss about the Dorian mode. This scale begins on the 2nd degree of the C major scale going up an octave. Now, its pattern is then like a natural minor scale with a raised sixth degree. The notes are D E F G A B C D.









I hope by now you have figured out how the rest of the modal scales are constructed. For the Phrygian scale on the C major scale, you only begin with the 3rd degree of the C major scale and go up an octave. It is very essential to remember the patterns formed in each scale.







































We will be discussing this topic in a more elaborate manner in later chapters, after we have discussed other topics which are pre-requisites of this topic. I hope this little illustration somehow gave you an idea as to how modal scales are made.