The Notes of the Harmonica -  This will give you a note chart for a Key of C Diatonic Harmonica.  This is what most beginning harmonica players will play.

How to play a single note - How to get a clear voicing of one note at a time.

How to Bend A Note -  Explanation on what bending a note is and how to bend a note.

Breathing - Just a brief discussion on how you should breath.