How to Play a Single Note on the Harmonica
Part of the Harmonica For Dummies Cheat Sheet
To play a single melody note on the harmonica, use your mouth to isolate a single hole. Next, play the note by drawing or blowing air through the harmonica with either a tongue block or a pucker:
Embouchure is what you do with your mouth when playing a musical instrument. The pucker and tongue block are the two most commonly used embouchures.