GNOME Terminal is a terminal emulator for the GNOME desktop environment that allows users to access a UNIX shell while using their graphical desktop. To open Terminal, users can search for it on the Dash or press Ctrl + Alt + T. The display prompt includes the username, computer name, and current directory. Basic commands demonstrated include pwd, ls, cd, touch, mkdir, rmdir, and cat. File permissions can be viewed and modified using ls -l and chmod. Ownership of files and directories can be changed with chown.

1. GNOME Terminal Basics
GNOME Terminal is a terminal emulator for the
GNOME desktop environment written by Havoc
Pennington and others.
Terminal emulators allow users to access a UNIX
shell while remaining on their graphical desktop.

2. GNOME Terminal Basics
To Open Terminal:
→ Search for Terminal on Dash.
Or,
→ Press Ctrl + Alt + T

3. GNOME Terminal Basics
About display prompt:
khassan@Ubuntu:~$
user@computer:~$
~ Represents Home directory.
$ Represents the user.

4. GNOME Terminal Basics
Show Present Working Directory:
→ user@computer:~$ pwd

5. GNOME Terminal Basics
List all files and folders in current directory:
:~$ ls [ Lists color coded files and folder names.
Blue names are directories, Light blue
names are protected directories, White
names are files and Green names are
executable files.]

6. GNOME Terminal Basics
--help:
To see options and other details for any command:
:~$ ls --help

7. GNOME Terminal Basics
Clear:
To clear screen:
$ clear
[ This command clears the screen but you can still find
previous commands by pressing uparrow key. ]

8. GNOME Terminal Basics
Change directory:
$ cd / [goes to the root directory.]
$ cd [goes to home directory from anywhere.]
$ cd Desktop/
~/Desktop$ pwd
[ /home/username/Desktop ]
$ cd ../ [ Up one directory]

9. GNOME Terminal Basics
Make Directory:
~/Desktop$ mkdir “Test Directory”
Or,
~/Desktop$ mkdir -m 777 “Test Directory”
[ -m option represents mode like chmod.
The directory name has a space and so the
quotation mark. ]

10. GNOME Terminal Basics
Remove Directory:
$ rmdir directoryName

11. GNOME Terminal Basics
To Create a File:
$ touch filename
[ file will not be created if the file already exists. ]
$ >filename
[ fill will be created and replace previous one. ]
$ >>filename
[ as touch ]

12. GNOME Terminal Basics
Editing a file using any editor:
$ gedit filename.txt
[ gedit is the notepad like editor in Ubuntu. ]
$ nano filename.txt
$ vim filename.txt

13. GNOME Terminal Basics
CAT ( Short for concatenate. )
Display contents of one or multiple files.
$ cat test.txt test2.txt
There are lots of other uses of cat command.
Read: http://www.tecmint.com/13-basic-cat-command-examples-in-linux/

14. GNOME Terminal Basics
:~$ su
Substitutes user or switches user to root.
In Ubuntu root user is disabled by default. It has no password.
:~$ sudo touch textfile.txt
Gives root privileges for a single command. Here that single command is
touch.
:~$ sudo -i
Switches user to root using normal users password. Exit will change the
prompt to normal user.

15. GNOME Terminal Basics
File Permission 01
File permission symbols:
u = user (owner)
g = group (group)
o = other (other)
- = not / normal files
d = directory
l = link
r = read = 4
w = write = 2
x = execute = 1
4 + 2 + 1 = 7

16. GNOME Terminal Basics
File Permission 02
To see the file permission details use ls -l. This option is for long
list of file permission.
khasan@KHasan:~$ ls -l
total 48
d rwx r-x r-x 3 khasan khasan 4096 Nov 29 07:49 Desktop
d rwx r-x r-x 2 khasan khasan 4096 Nov 21 02:45 Documents
d rwx r-x r-x 3 khasan khasan 4096 Nov 26 18:50 Downloads
- rw- r-- r-- 1 khasan khasan 8980 Nov 21 02:30 examples.desktop
G OU

17. GNOME Terminal Basics
File Permission 03
To change or edit files that are owned by root,
sudo must be used.
Changing file permissions for a particular
user/group/other:
chmod u/g/o+r/w/x filename
Ex:
chmod o-w-x filename

18. GNOME Terminal Basics
File Permission 04
To change file permission for all types of user:
[ To change or edit files that are owned by root, sudo must be used. ]
chmod -R ugo filename
Ex:
chmod -R 777 filename
4 = Read, 2 = Write, 1 = Execute, 0 = none
4+2+1 = 7

19. GNOME Terminal Basics
File Permission 05
Change Ownership:
sudo chown -R username:group directory
will change ownership (both user and group) of all files and
directories inside of directory and directory itself.
sudo chown username:group directory
will only change the permission of the folder directory but will leave
the files and folders inside the directory alone.

20. GNOME Terminal Basic
To Be Continued...