This is a 20-page PDF that explains major and minor keys, key signatures, and common chord progressions for popular keys. All musicians; piano, guitar, voice will benefit form this PDF.
Finding the major key from a minor chord is simple, with an easy trick. All tricks that help in playing a needed chord are explained in this simple reference book. Knowing the order of sharps and flats is essential to understanding what key a piece is in. Everyone can chord.