YYYY-MM-DD is the best date format and here's why:
- Putting the year first instantly frees you from US/EU date ambiguity, as it makes it obvious that the date comes straight after the year.
- Sorting dates alphabetically also sorts them chronologically.
- Dots and slashes are problematic in file names; hyphens are standard.
- It makes dates increment from the right-hand side, just like numbers do.
- It follows the ISO 8601 international standard.
- It looks badass.
All other date formats are inferior. There will be no further discussion on the matter.
– Rich