Command Line Tutorial for Beginners Ubuntu 16.04 Xenial LTS

November 6, 2017 | By the+gnu+linux+evangelist.

Command Line Tutorial for Beginners Ubuntu 16.04

Hi! The Tutorial Presents you a Command Line Tutorial for Beginners on Ubuntu 16.04 Xenial LTS GNU/Linux.

And the Command Line Ubuntu 16.04 Tutorial is Step-by-Step and you Can Just Getting-Started Following and Practicing each Command without any Harm for your System :)

But this is Just a “Quick & Dirty” Introduction to the Command Line by Example on the Bash Shell.

Now I strongly Recommend you to “Take it Easy” but to continue Experimenting with constancy, because as always is only the “Practice Makes the Master“! ;)

Most noteworthy: it’s fundamental you “Get your Hands Dirty” following along this guide and Execute the Commands as they are harmless for your System.

Especially Relevant: at the same Time I should like you take some FUN by my creative writing, and uncover the Magical Powers of the Shell in making the arid Silicon blossom Poetically. :))

Finally, the Commands here included are valid for the Default Linux Bash Shell and also for the Bourne, C, TC and Korn Shells…

Command Line Tutorial for Beginners Ubuntu 16.04 Xenial LTS - Featured

Open Shell session
Ctrl+Alt+t on Desktop
Congratulations, you Achieved the 1st Step in Learning Linux!
Press “Enter” to Execute Commands on Console

In case first see: Terminal QuickStart Guide.

Most noteworthy: the Main Bash Shell Commands are simple Abbreviations of the Corresponding World.

2. Listing

Now try to List the Directory’s Contents
To List the Directory you are in execute:
```
ls .
```
The “.” is optional and meaning the Location you are in.
[See how the Command “ls” is just an Abbreviation for Listing!]
The default Location each time you open a New Terminal Window is the Home Folder.
So the Output of the Command should be very similar to this:
```
Desktop/    Downloads/  Pictures/   tmp/
Documents/  Music/      Templates/  Videos/
```
Here the Entities with a Trailing Slash are Directories.
Again to List the Downloads Folder inside on your Home, run:
```
ls ~/Downloads
```
Or also:
```
ls $HOME/Downloads
```
Where “$HOME” is an Environment Variable always containing your User’s Home Path.
Next to List the Main System’s Root Directory:
(The Root of What? Of the System’s Directory Tree. The Trunk, all the other Directories are Branches.)
```
ls /
```
So possibly to List the “usr” Directory:
[Again an Abbreviation for “User System Resources“]:
```
ls /usr
```
Finally, to List the “bin” Branch:
[Again an Abbreviation for “Binaries” (The Executables)]
```
ls /usr/bin
```

3. Changing Folder

Next practice the Change Directory directive
Change to the Root Directory:
```
cd /
```
[Again find out how “cd” is an Abridgement for “Changing Directory“]
Then Go to /usr/bin:
```
cd /usr/bin
```
Now to Navigate Back to the Parent use the “..” option.
So non to Return to the Root of the Directory Tree you may play:
```
cd ../..
```
(It’s like to say: ‘One Step Back and then One Step Back’ again)
Finally, to Return Home is simple as:
```
cd  
```
Then to Verify you are in that Location Use:
```
pwd
```
[In this case the “pwd” Command is a Shortcut for “Print Working Directory“]
Hey Congratulations! you achieved the First, Step-by-step Walk into the Linux Directory Tree! :)

Especially relevant, about the Shell Terminology, there are 3 different Entities named as “Root”:

The System’s Directory Tree Root: /
The root User’s Directory: /root
The root User: the SuperAdmin that can Execute Any Command

4. Making Folders

Again experiment yours Creative powers
Making a test Directory like:
```
mkdir $HOME/livingroom
```
[See here again how “mkdir” is an Abbreviation for “Making Directory“].

How you should have already understood, $HOME and ‘~‘ are both synonymous of your’s Home Folder.
And the Home Directory is where your User Contents are Stored by Default.

Moreover, to enhance your Memorization and Fun I rightly Use some Metaphoric term. So here you can Immagine a directory like a Room into your Home :)

Try Making Multiple Directories at once with:
```
mkdir $HOME/bedroom $HOME/bathroom $HOME/garden
```
Try to use the “ls” Command to Check your creative Work:)
```
ls ~
```
Finally, use the ‘touch‘ Command to Make a New Empty File:
```
touch $HOME/livingroom/box
```
And how you could already have perceived, in my creative Examples I make use of the following Mnemonic Linking:
- Directory -> Spatial Entity
- File -> Thing
And so in the Previous Command to an “Empty File” corresponds a natively “Empty Thing” like a “box”, or otherwise you may take it as a simple Label/Name ;)

5. Copying Stuff

Experiment How to Copy Directories and Files.
- To Copy a Single File:
  * As in the other cases here ‘cp‘ is the Abbreviation for ‘Copy‘ *
```
cp $HOME/livingroom/box $HOME/bedroom/
```
  You see how in this Example we moved our ‘box’ from the ‘livingroom’ to the ‘bedroom’ :)
  
  Now verify the correctness of the operation Listing your’s bedroom contents:
```
ls $HOME/bedroom/
```
  And the Output will exactly display as:
```
box
```
- Now for Instance to Copy a Single Directory inside to another do:
```
cp -r $HOME/livingroom $HOME/garden
```
  List the ‘garden’ contents:
```
ls $HOME/garden
```
  And you’ll Find:
```
livingroom
```
  Now you have also a ‘livingroom’ copy into your ‘garden’ O:
  
  Moreover, to Copy-Duplicate-Rename a Directory:
  
  First, to be sure you are again into the $HOME area:
```
cd 
```
  And then Make a newly duplicated room do:
```
cp -r ./livingroom ./room
```
  Finally, to Copy-Displace-Rename at the same time:
```
cp -r $HOME/livingroom $HOME/bedroom/wardrobe
```
  By the way with this “magically crazy” Command we have trasformed our ‘livingroom’ into a ‘wardrobe’ inside to the ‘bedroom’ :))

6. Moving Stuff

Next Experiments the Dynamics of Files and Directories
And in this Moving dimension Files or Directories are taken as the Same.
[Again find out here how the “mv” Command is a Contraction of “Moving“]
So now for instance Make and Empty ‘bottle’:
```
touch ~/livingroom/bottle
```
And then we Displace it in another Room:
```
mv ~/livingroom/bottle ~/bedroom/
```
Then verify Listing the ‘bedroom’ contents:
```
ls ~/bedroom/
```
And what you Find? The:
```
bottle
```
Also if only an empty one, sorry :))

Again you can Move & Rename at the same time like:
```
mv ~/bedroom/bottle ~/bathroom/can
```
Again we have “magically changed” an empty “bottle” inside the “bedroom” in an empty “can” inside to the “bathroom”. :))
And as I said in the introduction the Command for Directories works the Same!
So now again like “Alice in the Wonderland” we Reshape the Folder “livingroom” in the “garden” into a “teapot” in the bedroom! :}}
```
mv ~/garden/livingroom ~/bedroom/teapot
```
Patiently Verify it with:
```
ls ~/bedroom/teapot
```
Finding What?
```
 
```
Simple :) Emptiness! :}

7. Annihilating

Finally, we try investigating our Magical Destroying Powers
Deleting Directories and Files!

Especially Releant: in a Working Environment you should Triple Check the Commands Before Execution…
Because in the Shell Environment there’s No Trash Bin and so the stuff is directly Annihilated!!!

[And as you may have already wittily perceived, here “Removing” is just Resumed in “rm“]
- How Removing Files.
  
  First, we Wipe Out the ‘box’ in the ‘livingroom’ with:
```
rm $HOME/livingroom/box
```
  Check it with:
```
ls $HOME/livingroom/
```
  Now we try the same for Multiple Entities…
  First, we Make a Copy of the ‘can’ into then ‘bathroom’ in a ‘jar’ into the ‘bedroom’, Magically as before… :)) with:
```
cp $HOME/bathroom/can $HOME/bedroom/jar
```
  And now how to brutally Get Rid of Both? Simply like that:
```
rm $HOME/bathroom/can $HOME/bedroom/jar
```
- How Removing Directories.
  
  Now we Start to furiously Destroying our nice Home… [[[:
  First, we Raze the ‘livingroom’:
```
rm -rf $HOME/livingroom
```
  “-rf” is a combination of Flags. “r” for Recursively and “f” for Forced
  And finally, finally, we simply Desert All-in-one the Remaining Habitats:
```
rm -rf ~/bathroom ~/bedroom ~/garden
```
Sorry, we have Turned our Home into Empty Space, but What a JOKE! {{{:
And to Execute a Command as SuperUser
This should be the Recommeded practice to Operate as root on Linux File System:
```
sudo su -c 'myCommand'
```
Or:
```
sudo myCommand
```
So for instance to List the Protected root Directory try to run:
```
sudo ls /root
```
Finally, to Login as root Admin User
And this is only advisable in case you have to work as SuperUser for many Commands in succession…
So to Login:
```
sudo su
```
If Got “User is Not in Sudoers file” then see: How to Enable sudo

And then to Logout simply:
```
exit
```
To Protect your System from the potential Damage of an Hazardous Crazy Command Execution the Logout should be executed every Time your Setup is Achieved!
How to Set Permissions on Ubuntu File System

Ubuntu Permissions Quick Start

Setting Up Permissions on Ubuntu