some useful linux commands and their full forms

ACL                            Access control list.

awk                             Aho, Weinberger, and Kernighan.

BIOS                          basic input output system.

cd                               change Directory.

chmod                        change mode.

chown                        change owner.

CIFS                          common Internet File System

df                                disk free.

DHCP                        Dynamic Host Configuration Protocol.

DNS                           Domain Name System.

du                              disk usage.

ext2                            second extended file system.

ext3                            third extended file system.

ext4                            fourth extended file system.

fdisk                           fixed disk.

FTP                            File Transfer Protocol.

grep                            Global  regular expression print.

GRUB                        Grand unified Bootloader.

http                            HyperText Transfer Protocol.

ifconfig                       Interface Configuration.

IMAP                         Internet Message Access Protocol.

KVM                          Kernel Virtual Machine.

LVM                          logical volume manager.

MBR                          Master Boot Record.

mkfs                           make filesystem.

NFS                            Network file system

pop                             Post Office Protocol.

ps                                process status.

pwd                            present working directory.

rm                              remove.

RPM                          Redhat package Manger.

scp                              secure copy.

sed                              Stream Editor.

SGID                          set group id.

SMB                           Server Message Block

ssh                              Secure Shell.

su                               substitute user or switch user.

sudo                           substitute user do or super user do .

SUID                          set user id .

tar                              tape archive.

TFTP                         Trivial File Transfer Protocol.

umask                        User's File Creation Mask.

Vim                            Visual Improved

VSFTP                       very secure  File Transfer Protocol.

YUM                          Yellowdog updater modified.