Linux terminology

•su-bideen

( Root will assume the role of bideen and will move into bideen's profile)

ls Options:

-a, -l, -al, -lh, -R, -ltr, -i, -ld

/

: The root or very top directory in linux

•cd command

: Used to move from one directory to another

•du -h

: will display the components of your pwd including the size of each component

,Linux file system types include

:Ext, Ext2, Ext3, Ext4, JFS, XFS, Btrfs, ReiserFS, Swap,ZFS

/proc:

Because everything on Linux is a file, this folder is for processes running on the system,and you can access them and see much info about the current processes

/etc:

Contains configurations for the installed packages.

/var:

Contains system logs and other variable data.

/tmp:

Contains the temporary files.

/media:

Here are the external devices like DVDs and USB sticks that are mounted, and you can access their files from here.

-Journaling:

It is designed in filesystems to prevent data corruption from crashes and sudden power loss.

/sbin:

Like /bin, but binaries here are for root user only.

File System

On a linux system, everything is a file. If something is not a file, then it is a process. EXT4 is the default filesystem on most Linux distros. It is an improved version of EXT3, rock-solid and very stable

/opt:

Some optional packages are located here and managed by the package manager.

./root:

The home folder for the root user.

ll

This command is used to list the detail information of files and folder of a current directory.

/bin:

Where Linux core commands reside like ls, mv.

/dev:

Where all physical drives are mounted like USBs DVDs.

/boot:

Where boot loader and boot files are located.

/home:

Where every user will have a personal folder to put his folders with his name like /home/fabrice

/lib:

Where the libraries of the installed packages located.

/usr:

Where the utilities and files shared between users

/mnt:

Where you mount other things Network locations and some distros, you may find your mounted USB or DVD.

•cal command is a calendar command in Linux which is used to see the calendar of a specific month or a whole year.

cal

A filesystem .

controls how data is stored and retrieved. Without a filesystem, information stored in a storage medium would be one large body of data with no way to tell where one piece of information stops and the next begins.

•date command is used to display the system date and time. date command is also used to set date and time of the system. By default the date command displays the date in the time zone on which unix/linux operating system is configured. You must be the super-user (root) to change the date and tim

date

•du -

display directory size: du -sh /etc

•

echo $SHELL

•In Linux, there is a very useful command to show you all of the last commands that have been recently used. The command is simply called history, but can also be accessed by looking at your . ... By default, the history command will show you the last five hundred commands you have entered

history

echo

is one of the most commonly and widely used built-in command for Linux bash and C shells, that typically used in scripting language and batch files to display a line of text/string on standard output or a file

•ls -

list files and directories in bare format. Does not display details like file type, size,modified date, permissions and links.

•In computer software, logname (stands for Login Name) is a program in Unix and Unix-like operating systems that prints the name of the user who is currently logged in on the terminal. It usually corresponds to the LOGNAME variable in the system-state environment (but this variable could have been modified)

logname

•As the name suggest passwd command is used to change the password of system users. If the passwd command is executed by non-root user then it will ask for the current password and then set the new password of a user who invoked the command.

passwd

•stands for Print Working Directory. It prints the path of the working directory, starting from the root. pwd is shell built-in command(pwd) or an actual binary(/bin/pwd). $PWD is an environment variable which stores the path of the current directory.

pwd

•su

switch from one user to another

•ifconfig

system administration utility in Unix-like operating systems for network interface configuration. The utility is a command-line interface tool and is also used in the system startup scripts of many operating systems.

ip

used to assign an address to a network interface and/or configure network interface parameters on Linux operating systems. This command replaces old good and now deprecated ifconfig command on modern Linux distributions.

address (addr/a) -

used to display and modify protocol addresses (IP, IPv6).

•whoami command is used both in Unix Operating System and as well as in Windows Operating System. It is basically the concatenation of the strings "who","am","i" as whoami. It displays the username of the current user when this command is invoked. It is similar as running the id command with the options -un.

whoami