The file system is volume-oriented: the top level of the file hierarchy is a volume (disc, network share) prefixed by the file system type. To determine file type, the OS uses metadata instead of file extensions. Colons are used to separate the file system from the rest of the path; the root is represented by a dollar (codice_1) sign and directories are separated by a full stop (codice_2). Extensions from foreign file systems are shown using a slash (codice_3 becomes codice_4). For example, codice_5 is the root of the disc named "HardDisc4" using the Advanced Disc Filing System (ADFS) file system. filetypes can be preserved on other systems by appending the hexadecimal type as 'codice_6' to filenames. When using cross-platform software, filetypes can be invoked on other systems by naming appending 'codice_7' to the filename under .