The enumeration class representing the 12 months of the year.
January, month #01, with 31 days.
February, month #02, with 28 days, or 29 in leap years.
March, month #03, with 31 days.
April, month #04, with 30 days.
May, month #05, with 31 days.
June, month #06, with 30 days.
July, month #07, with 31 days.
August, month #08, with 31 days.
September, month #09, with 30 days.
October, month #10, with 31 days.
November, month #11, with 30 days.
December, month #12, with 31 days.
The number of the Month. January is 1, December is 12.