Directories are containers for files. Directories are named by filenames, which can be either strings or implementation-defined objects.
(directory? filename)
Returns #t if filename is the name of a directory, or #f if it is not, or the answer is not determinable.
(make-directory filename)
Creates a directory named filename. An exception is signaled if this cannot be done.
(delete-directory filename)
Deletes a directory named filename. An exception is signaled if this cannot be done.
See DirectoryPortsCowan.