The last whom posts wins.

[Delete This Username Please.]

CHDIR (CD) [d:]path
CHDIR (CD)[..]

Displays working (current) directory and/or changes to a different directory.

CHKDSK
(External)

CHKDSK [d:][path][filename] [/F][/V]

Checks a disk and provides a file and memory status report.

CHOICE
(Internal)

CHOICE [/C[:]keys] [/N][/S][/T[:]c,nn] [text]

Used to provide a prompt so that a user can make a choice while a batch program is running.

CLS (Clear Screen)
(Internal)

CLS

Clears (erases) the screen.

COMMAND
(External)

COMMAND [d:][path] [device] [/P][/E:(size)] [/MSG][/Y [/C (command)|/K (command)]

Starts a new version of the DOS command processor (the program that loads the DOS Internal programs).

COMP
(External)

COMP [d:][path][filename] [d:][path][filename] [/A][/C][/D][/L][/N:(number)]

Compares two groups of files to find information that does not match. (See FC command).

COPY
(Internal)

COPY [/Y|-Y] [/A][/B] [d:][path]filename [/A][/B] [d:][path][filename] [/V]
or
COPY [/Y|-Y][/A][/B] [d:][path]filename+[d:][path]filename[...][d:][path][filename] [/V]

Copies and appends files.

COUNTRY
(Internal)

COUNTRY=country code,[code page][,][d:][filename]

Used in the CONFIG.SYS file to tell DOS to use country-specific text conventions during processing.

CTTY
(Internal)

CTTY (device)

Changes the standard I/O (Input/Output) device to an auxiliary device.

DATE
(Internal)

DATE mm-dd-yy

Displays and/or sets the system date.

DBLSPACE
(External)

DBLSPACE / automount=drives
DBLSPACE /chkdsk [/F] [d:]
DBLSPACE /compress d: [/newdrive=host:] [/reserve=size] [/F]
DBLSPACE /create d: [/newdrive=host:] [/reserve=size] [/size=size]
DBLSPACE /defragment [d:] ]/F]
DBLSPACE /delete d:
DBLSPACE /doubleguard=0|1
DBLSPACE /format d:
DBLSPACE [/info] [d:]
DBLSPACE /list
DBLSPACE /mount[=nnn] host: [/newdrive=d:]
DBLSPACE /ratio[=ratio] [d:] [/all]
DBLSPACE /size[=size] [/reserve=size] d:
DBLSPACE /uncompress d:
DBLSPACE /unmount [d:]

A program available with DOS 6.0 that allows you to compress information on a disk.

DEBUG
(External)

DEBUG [pathname] [parameters]

An MS-DOS utility used to test and edit programs.

DEFRAG
(External)

DEFRAG [d:] [/F][/S[:]order] [/B][/skiphigh [/LCD|/BW|/GO] [/H]
DEFRAG [d:] [/V][/B][/skiphigh] [/LCD]|/BW|/GO] [/H]

Optimizes disk performance by reorganizing the files on the disk.

DEL (ERASE)
(Internal)

DEL (ERASE) [d:][path]filename [/P]

Deletes (erases) files from disk.

DELOLDOS
(External)

DELOLDOS [/B]

Deletes all files from previous versions of DOS after a 5.0 or 6.0 installation.

DELTREE
(External)

DELTREE [/Y] [d:]path [d:]path[...]

Deletes (erases) a directory including all files and subdirectories that are in it.

DEVICE
(Internal)

DEVICE=(driver name)

Used in the CONFIG.SYS file to tell DOS which device driver to load.

DEVICEHIGH
(Internal)

DEVICEHIGH=(driver name)

Like DEVICE, DEVICEHIGH is used in the CONFIG.SYS file to tell DOS which device driver software to use for devices; however, this option is used to install the device driver into the upper memory area.

DIR
(Internal)

DIR [d:][path][filename] [/A:(attributes)] [/O:(order)] [/B][/C][/CH][/L][/S][/P][/W]

Displays directory of files and directories stored on disk.

DISKCOMP
(External)

DISKCOMP [d:] [d:][/1][/8]

Compares the contents of two diskettes.

DISKCOPY
(External)

DISKCOPY [d:] [d:][/1][/V][/M]

Makes an exact copy of a diskette.

DOS
(Internal)

DOS=[high|low],[umb|noumb]

Used in the CONFIG.SYS file to specify the memory location for DOS. It is used to load DOS into the upper memory area and to specify whether or not the upper memory blocks will be used.

DOSKEY
(External)

DOSKEY [reinstall] [/bufsize=size][/macros][/history][/insert|/overstrike] [macroname=[text]]

Loads the Doskey program into memory which can be used to recall DOS commands so that you can edit them.

DOSSHELL
(External)

DOSSHELL [/B] [/G:[resolution][n]]|[/T:[resolution][n]]

Initiates the graphic shell program using the specified screen resolution.