Returns the month value in the Date object using local time.
The required dateObj reference is a Date object.
To get the month value using Universal Coordinated Time (UTC), use the getUTCMonth method.
The getMonth method returns an integer between 0 and 11 indicating the month value in the Date object. The integer returned is not the traditional number used to indicate the month. It is one less. If "Jan 5, 1996 08:47:00" is stored in a Date object, getMonth returns 0.