Just general rambles about your reply (which is merely a cheap way to mention something I did in VBScript :)

I prefer YY/MM/DD or YYYY/MM/DD since sorting is much easier. It may not seem like a big deal to Perl users, but imagine if others are forced to manipulate data in other languages, such as VBScript, which doesn't have native sorting.^*

In any event, even with Perl's robust sorting abilities, having a straight-forward sort on the dates is much easier to read than a lot of weird maps or greps or other things. Of course, if I have complex sorting, I usually stick it in a function with a descriptive function name.

Cheers,
Ovid

* I kind of feel sorry for some of the VBScript programmers I left behind. I am so used to shift, pop, sort, and so many other handy tools to use with lists and arrays that I wrote a "Perl functions" library in VBScript. Much of my VBScript code read like "baby Perl" (though only in parts where I thought the overhead wouldn't kill a language that was not designed for such functions).

It isn't unamed, it is ISO 8601. It is the internationally standardized date format (except the standard specifies that you use "-" instead of "/", which is a good idea as it is easier to read that way ["/" looks too much like a "1" to too many cases] and also doesn't require escaping).

See international standard date format.