Partitioning is the process of dividing and naming the
hard disk so that the Operating System can recognize the media for further processing.
There can be one or more partitions in a given hard disk. A maximum of four
partitions can be placed on any hard disk. These are called primary
partitions. Only one partition may be designated, at any given time, as active.
The primary partition will be used for booting the system. DOS will only
recognize the active primary partition. Any other primary partitions will be
ignored. One of the four partitions may be designated as an extended DOS
partition. This partition may then be subdivided into multiple logical
Directory Structures (root directory, subdirectories, etc)
Navigate the directory structure
The directory structure consists of Root directory, other directories,
sub-directories, and files. The root directory is at the root of the file
system. It is intuitive to navigate, create, and delete directories using
Windows Operating System. While using DOS, you need to use command line
interface (CLI) for the same. The following commands are used in DOS for
navigating the file system:
The command "cd" is used to change the present working directory to
The command "md" is used to create a new directory by name
"dir1"; md is short for make directory.
The command "rd" is used to remove the specified directory; rd is
short for remove directory.
Another command frequently used is "dir", as shown below.
It lists all directories and files with the given path. In the example above,
the command is given at the root directory (C:).
Important File attributes supported by DOS are given below:
Read-Only: With a file marked Read-Only, most software will refuse to
delete or modify it. For example, DOS will give "Access denied"
message if you try to delete a read-only file.
Hidden: If the file is marked hidden then it is hidden from viewing
using the "DIR" command. DOS will not display the file when you type
"DIR" unless a special flag is used.
System: This flag is used to tag important files that are used by the
system and should not be changed or removed from the disk. In essence, this is
like more like a read-only flag.
Volume Label: Every disk volume can be assigned an identifying label,
either when it is formatted, or later through various tools such as the DOS
command "LABEL". The volume label is stored in the root directory as a
file entry with the label attribute set.
Directory: This is the bit that differentiates between entries that
describe files and those that describe subdirectories within the current
Archive: Backup software usually allows the user to do an incremental
backup, which only selects for backup any files that have changed since the last
backup. The Archive bit is used for this purpose. When the backup software backs
up ("archives") the file, it clears the Archive bit. Any subsequent
modification to the file will make the archive bit set. When the backup software
runs again, it knows that the file has been modified since previous back-up, and
backs it up again (and ofcourse, clears the archive bit).
In DOS, you can use ATTRIB command to modify any file attributes. Using
Windows, by looking at the file's properties through Windows Explorer (or any
similar software), you can modify file attributes.
File compression is a technique that compresses program or data files so that
they occupy less disk space. The file is decompressed before use. Note that
recompressing an already compressed file usually makes the file slightly larger
due to compression overhead. File compression can be performed
by the operating system automatically, or it can be manually performed using a file
compression program. Examples of file compression programs are winzip, and pkzip.
File encryption is the process of encoding information in order
to make it secure from unauthorized access, particularly during transmission.
File decryption is done to reverse the encryption before using the file.
There are mainly two types of encryption schemes. One is based on Symmetric
Keys, and the other is based on Asymmetric Keys.
Windows 2000 uses compression similar to DriveSpace in windows 98, but unlike
DriveSpace which compress entire volumes, it can compress individual files and
Using Windows 2000, you can compress files and folders only on drives
formatted with NTFS. Note that compressed files and folders cannot be encrypted.
If you add or copy a file into a compressed folder, it is compressed
automatically. If you move a file from a different NTFS drive into a compressed
folder, it is also compressed. However, if you move a file from the same NTFS
drive into a compressed folder, the file retains its original attributes.
To compress a file or folder
1. In explorer select the file or folder you want to compress, then right
click -> Properties
2. Check on the "Compress contents to save disk space"
To remove compression from a file or folder, just uncheck the "Compress
contents to save disk space box"
Encryption: Windows 2000 includes greater security than other versions of
windows, with its Encrypting File System (EFS). It is based on public and
private key encryption. The file system automatically generates an encryption
certificate for the user along with a private key. You can encrypt individual
files or folders, only on the NTFS file system.
When a user is logged on, they don't have to decrypt files to use them EFS
automatically detects an encrypted file, locates the users private key and
decrypts the file.
To encrypt a file or folder
1. In explorer select the file or folder you want to encrypt, then right
click -> Properties
2. Choose advanced button to display the advanced attributes
3. Check the "Encrypt Contents To Secure Data" box
To remove encryption from a file or folder, just uncheck the "Encrypt
Contents To Secure Data" box.
You can also encrypt file and folders from the DOS command prompt using
cipher.exe If you do not use any command line options cipher will just display
the encryption status of the folder.
cipher [/e | /d]
[/s:dir] [/i] [/q] [dirname]
- /e Encrypts specified directory
- /d Decrypts specified directory
- /s : dir Specifies the directory to encrypt or decrypt
- /i Ignors errors
- /q Specifies a directory