What are altered chords and how can they be used tastefully?

They are chords that have one or more notes from the diatonic scale altered by a half step.  Used tastefully they add tension and drama

Explanation:

Hi, an altered chord is a chord that has one or more notes from the diatonic scale altered by a half step.

The alteration can be raising the note by a half step or lowering it by a half step.

These types of chords can be used tastefully, adding tension or drama to the progression of chords, or part of a song.

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