What are the different musical scale modes and how are they used in music composition and performance?

Musical scale modes are different arrangements of notes within a scale that create distinct sounds and moods. The main modes are Ionian, Dorian, Phrygian, Lydian, Mixolydian, Aeolian, and Locrian. They are used in music composition to create variety and interest in melodies and harmonies. In performance, musicians can use modes to improvise, add color to a piece, or create a specific mood.