what are the DOS commands that are categorized as internal? which are the external?
Answers:
If it's in the file: command.com, then it is internal, otherwise it is external.
Other answers:
The following is a list of MS-DOS version 5.0 internal and external commands. The internal commands reside in COMMAND.COM, which loads into memory when the computer system is started; these commands do not reside on disk. The external commands are files that do reside on disk and have an extension of .COM, .EXE, or .BAT. Both command types are executed from the MS-DOS prompt.
Internal Commands
BREAK
CALL
CHCP
CHDIR(CD)
CLS
COPY
CTTY
DATE
DEL(ERASE)
DIR
ECHO
EXIT
FOR
GOTO
IF
MKDIR(MD)
PATH
PAUSE
PROMPT
REM
RENAME(REN)
RMDIR(RD)
SET
SHIFT
TIME
TYPE
VER
VERIFY
VOL
External Commands
APPEND.EXE
ASSIGN.COM
ATTRIB.EXE
BACKUP.EXE
CHKDSK.EXE
COMMAND.COM
COMP.EXE
DEBUG.EXE
DISKCOMP.COM
DISKCOPY.COM
DOSKEY.COM
DOSSHELL.COM
EDIT.COM
EDLIN.EXE
EMM386.EXE
EXE2BIN.EXE
EXPAND.EXE
FASTOPEN.EXE
FC.EXE
FDISK.EXE
FORMAT.COM
GRAFTABLE.COM
GRAPHICS.COM
HELP.EXE
JOIN.EXE
KEYB.COM
LABEL.EXE
MEM.EXE
MIRROR.COM
MODE.COM
MORE.COM
NLSFUNC.EXE
PRINT.EXE
QBASIC.EXE
RECOVER.EXE
REPLACE.EXE
RESTORE.EXE
SETVER.EXE
SHARE.EXE
SORT.EXE
SUBST.EXE
SYS.COM
TREE.COM
UNDELETE.EXE
UNFORMAT.COM
XCOPY.EXE
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