The harmonica is most commonly used in blues and American folk music, but is also used in jazz, classical music, country music, rock and roll, and pop musicThe harmonica is most commonly used in blues and American folk music, but is also used in jazz, classical music, country music, rock and roll, and pop musicThe harmonica is most commonly used in blues and American folk music, but is also used in jazz, classical music, country music, rock and roll, and pop musicThe harmonica is most commonly used in blues and American folk music, but is also used in jazz, classical music, country music, rock and roll, and pop musicThe harmonica is most commonly used in blues and American folk music, but is also used in jazz, classical music, country music, rock and roll, and pop music