Here's the breakdown of the 7-note "Diatonic" Scales:

 MAJOR              1     2      3     4       5       6       7     8(1) 

 MELODIC MINOR      ............b3....................................

 HARMONIC MAJOR     ..................................b6..............

 HARMONIC MINOR     ............b3....................b6..............


 NOTE:
 Understanding the functions of these four scales can greatly enhance
 one's awareness of what transpires in music on this planet.