The "cd" command allows the user to specify a new working directory. The working directory is held in the $PWD shell variable. If a partial pathname is given, a full path is generated using the existing $PWD variable. If no pathname is given, the user is returned to the $HOME directory.
Pathnames consist of volume and directory names separated by ':' characters. Pathnames may be "quoted", and must be when a volume or directory name contains a space.