The routine for directory listing is called CATALOG (shades of Apple DOS, and Heath's HDOS); for deleting, the routine is ERASE (shades of CP/M).
Early, abandoned steps toward UNIX: MS-DOS 2.2 supported the SWITCHAR variable in config.sys; if set to anything but "/", the directory separator would be slash -- just like Xenix and UNIX; if set to "-" you would type "DIR -W C:/foo/bar" for a wide listing of what generally would be called C:\FOO\BAR
vBulletin is a proprietary forum software.
No, vBulletin is a software package, or a program, or even "vBulletin is software" -- but never "a software." You don't have "a hardware" or "an information" or "a clothing" -- you have a piece of hardware, a piece of information, a piece of clothing, and a piece of software. Grammar check, please.