Types of DOS Commands:
There are two types of DOS Commands.These are:
i. Internal Commands
ii. External Commands Internal
Commands: are the part of command .com file of DOS. During booting process,"Command .com" file is automatically loaded into the RAM. These commands are available from RAM. It is because these are known as internal commands. These commands have no filename and these are the part of "command.com" file. Some DOS internal commands are : CLS,DATE,TIME,DIR,COPY,DEL,VER etc.
ii.External Command: The command of DOS stored on the disk with their own filenames are known external commands. It is loaded into memory from disk excution. The file name extensions of external command is COM or EXE. Some of DOS external commands are FORMAT,CHKDSK,DELTREE,XCOPY,ATTRIB,DISKCOPY,SYS etc.