A reference chart for the 10-hole major diatonic harmonica and chromatic harmonica. Includes for the diatonic harmonica: 1) A chart of notes for all major keys and relative positions; 2) Note layout for standard draw and blow bending; 3) Note layout for over-bending; 4) Lee Oskar Altered Tunings; and 5) The most common scales. For chromatic harmonica, the chart shows 1) Note layout for 10, 12 and 16 hole chromatic harmonicas; and 2) Complete major and minor scales along with common modes.