TYPE OF COMMANDS

TYPES OF DOS COMMANDS:-

            A commamd is set of instruction to carry out specific task.DOS provides commands to manage file and folders,utility commands for operating system service,commands related to disk operations and commands for system configuration .All these MS-DOS commands are categorized as internal commands and external commands.

INTERNAL COMMANDS:-

            Internal commands are part of command interpreter file COMMAND .COM .Internal command are loaded to memory during booting .They can be executed from any DOS prompt .These are called memory resident command because they are always in memory as a part of COMMAND.COM file. As these commands are memory resident commands they execute fast .They are not listed by the command as they are part of COMMAND .COM file .

Some Internal Command Are:-

            DATE,TIME,COPY CON,TYPE,REN,DEL,COPY,MD,CD,RD,DIR,PROMPT,VER,VOR etc.

EXTERNAL COMMANDS

            External  commands are those commands which are stored as separated command file in the disk.The extensions of these files are.com and .exe.They are not memory resident commands.So the command is loaded in the memory only if that command is used.These command files are visible because they are separate files not part of any other file.The execution of external command is slow compared to internal commands because they load at the time of execution. Some External commands are as follows:

            CHKDSK,FORMAT,LABEL,PATH,DELTREE,SYS,DISKCOPY,DISKCOMP,TREE,EDIT,ATTRIB etc.