Date format: YYYY-MM-DD
On my Dekkerware web site, I use the following date format:
So for example, 2007-02-04 represents the fourth day of February in 2007.
This is an international standard date format, according to ISO 8601. See also:
Niels Dekker, 2007-10-17
Numeric representation of Dates and Time
The ISO solution to a long-standing source of confusion