A virtual directory is a way of restricting what pages get shown out of a real directory. It works by tacking on 'virtual' directories after the real directory (ie, as subdirectories) to tell DWiki what you want to see.
Virtual directories restrict pages based on their most recent modification time. There are three versions available:
<year>/[<month>/[<day>]], all as
digits. Only pages most recently changed in the time period get
selected.latest/<howmany>. They show just the
most recently changed <howmany> pages.oldest/<howmany>. They show just the
least recently changed <howmany> pages.range/<start>-<end>. They show the
start'th to the end'th most recently changed page.All pieces of a virtual directory must really be virtual. If you
have a directory Foo/ with a Foo/2005/ subdirectory (or file), you
cannot use the virtual directory Foo/2005/05/ to see things from May
of 2005 in Foo/. Moral: let DWiki organize things based on time for
you, don't do it yourself.
Virtual directories are paid attention to by some renderers, which are generally used in some views. You can get the full list in TemplateSyntax.