Guitar Chords 101More than just a catalog of chords, this book is designed to help any player find, play and properly use chords. It will quickly become a powerful tool and an important aid to your musical development. The book functions in three different ways: 1) As a chord dictionary look up any unfamiliar chords you encounter; 2) As a chord substition guide learn about how chord substitutions work, when to use them and which chords may be substituted for others;