The Dorian Modal Scale

The Dorian scale is an organization of pitches encompassing the Dorian Mode. If you are looking at the piano, it would be all the white notes from D to D. The pattern of tones are as follows:

Tone, semitone, tone, tone, tone, semitone, tone 

The order is in reverse for the descending scale. 

Listen to this Dorian scale and then repeat the recording to sing along. Notice where the tones and semitones fall.

T = Tone (Whole Tone)

ST = Semitone