Different tasks performed by DOS commands

1. Displaying and changing date and time.
2. Clearing the screen.
3. Displaying version of DOS and volume label.
4. Creating, displaying, copying, renaming, erasing files.
5. Displaying directories and file of a disk.
6. Creating, changing and removing directory.
7. Changing system prompt (or message).
8. Setting path (or way) to search desired directory and files.
9. Copying an entire diskette.
10. Formatting diskettes.
11. Checking diskettes or hard disk.
12. Editing text, copying directory, including files in sub directories.
13. Making Backups and writing back from backups.
14. Transferring DOS system files to diskette or hard disk
15. Running desired programs.
16. Printing contents of a file etc.

General rules for using MS-DOS

• DOS commands are entered at DOS system prompt (e.g. C:\>).
• DOS commands are invoked by entering the name of command.
• The maximum length of a DOS command is 127 characters.
• Commands can also be entered using DOS SHELL ( a graphic user interface).
• A command followed by question mark option (/?) on the command line does not execute the command, but displays the description of particular command's syntax and its usage.
• Special function keys can be used for entering repetitive commands.
• Internal command of DOS execute at any time whereas External commands of DOS can be executed in the presence of program files.