Asciibetically

The elements of the array are ordered ASCIIbetically.

Perl’s built-in sorting behavior is as though the elements were compared ASCIIbetically with the cmp operator: […]

Then, the Help Compiler ASCIIbetically sorts each group according to its number (which can actually be any alphanumeric string, but for sanity’s sake you should stick to 4-digit numbers, incremented by tens, like 0010, 0020, etc.).

If you need to sort text ASCIIbetically, then you should seriously consider running your files through a script that enforces pure printable-ASCII content.