Chordal harmony is all about chords and chord progressions.
Chord is the static element of harmony, chord progression is the dynamic element. A chord focusses on how notes are grouped together at a single point in time. A chord progression focusses on how chords relate to each other through time.
Chordal harmony differs from drone harmony, parallel harmony, counterpoint and self harmony because all these other approaches are melody-based whereas chordal harmony can be written with or without a melody.
All the basics needed to write chordal harmony are covered in the following chapters:
At this point, the emphasis moves from a chord containing a minimum of two notes to a chord containing a minimum of three notes. The remaining chapters in the section deal exclusively with a chord that contains three or more notes:
Along the way we address some general issues in harmony. We will determine what a chord is and does, look at the relevance of consonance and tonality to a chord, consider when a chord is complete, and see how chords relate to each other and to key and scale. We will explain why some definitions of a chord require a minimum of two notes whilst others require three. These are all pretty fundamental issues in harmony so gird your loins and be prepared for some lengthy discourse.