1. DISK OPERATING System MS-DOS

2. MS-DOS Microsoft Disk Operating System (MS-DOS) is a single user, single tasking operating system. DOS is a command-line, text-based/non- graphical user-interface commonly referred to as Character Based User Interface (CUI).

3. Guide Lines for DOS Command How to start DOS:- 1.START-> RUN-> type command prompt or cmd -> ENTER. 2.START -> PROGRAM -> ACCESSORIES -> COMMAND PROMPT ->ENTER. 3.The DOS prompt consist the default drive letter and the character ‘>’. Ex. C:\> is the DOS prompt that denotes C as the default drive. 4.When a command has finished executing, the DOS prompt reappears on the screen if no message appear before the DOS prompt returns, it means the command has been executed successfully.

4. 5. It is not a case sensitive language, we can type the commands in both the cases (Upper case, lower case or the combination of both). 6.Commands starts executing only after you press the enter key. 7.It does not allow using long file names. The user is restricted to eight-character file names with three-character extensions. 8.Drives are referred to as source drive and target drive. A source drive is the drive you transfer information from. And target drive is that you transfer information to.

5. Operating System Performs- Input/Output Management. Memory Management. File Management. Files and programs deletion and addition. It controls all the peripheral devices.

6. Type Of Command There are two types of commands. 1. Internal commands. 2. External commands  Internal Commands:- Internal Commands are the simplest, most commonly used commands and executes immediately because they are part of a file, named COMMAND.COM

7. DIRDIR MDMD CDCD RDRD COPYCOPY RENREN DELDEL COPY CONCOPY CON TREETREE TYPETYPE EXITEXIT DATEDATE TIMETIME VERVER HELPHELP EDITEDIT CD..CD.. CD\CD\ Followings are some Internal Commands

8. DIR- To display all directories on the screen. C:\>dir DIR/P- Page wise DIR/W- width wise DIR/A- Shows all files & directories. DIR/S- Shows the directories, sub directories & files. DIR/OS/P- Size wise DIR/ON/P- Alphabetically (A to Z)

9. EXIT-Exit command is used to come out side from the dos screen. C:\>exit CLS- Clears the screen. C:\>cls MD- this command is used to make a directory. We need to give the name. C:\>md C:\>md india

10. CD- It is used to go inside the directory. C:\>cd C:\>cd India CD.. And CD\- cd.. Command is used to come out to the root directory step by step. And cd\ is used to come out to root directory at once. C:\>red\black\green>cd.. C:\>red\black>cd..

11. C:\>red>cd.. CD\ command C:\>red\black\green>cd\ C:\> RD- means remove directory. It is used to remove the directory, before that directory must be empty. C:\>rd C:\>rd india

12. DEL- it is used to delete a particular file or group of file. C:\>del C:\>del file1 To delete group of file C:\>del *.* REN- it is used to rename the file. C:\>ren C:\>ren F1 F2

13. COPY- it is used to copy the content of a file. C:\>copy C:\>copy F1 F2 DATE- Displays the current date and prompts the user to enter the new date. C:\>date

14. TIME - Displays the current time and prompts the user to enter new time. C:\>time VOL - it is used to see the volume level of a disk. i.e each disk is given a volume. C:\>vol

15. COPY CON- it is used to create a file. C:\>copy con C:\>copy con jims TYPE- it is used to see the content of a file. C:\>type C:\>type jims

16. EDIT- it is used for opening the file in a editor. editing & modifications can be done in the editor. C:\>edit C:\>edit jims Ver- it displays window version. C:\>ver

17. DELTREE- it is used to delete directory and all the sub-directories and files in it. C:\>deltree C:\>deltree temp Tree- tree command is used to show all director and its sub-directory in tree form. C:\>Tree

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