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Hello everyone and welcome back to this lecture.

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Now in this trial we'll be covering some of the basically Nick's comments and in order for you to get

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to know Linux better.

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The good way would be to start off with learning these basic commands that I will teach you right now.

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So to start off we just want to open up our terminal which is this icon right here.

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So just click on it.

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It should open up this terminal.

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And if you want to you can enlarge it a little bit so you can see things better right here from this

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box right here will be running all our programs.

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Most of our programs and we will be running all of the other comments so you better get used to this

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as we will be doing most of our work from here.

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So the first comment I want to show you is be WD which stands for print working directory.

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So it basically just prints out the current directory that you are in which for in my case is slash

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root.

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Now if we want to change the rectory we would firstly need to know what sub directories are in slash

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root in order to list all the files and all the sub directories in slash root.

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We can just type here L S which will show us all of the current sub directories that are located in

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the slash root directory as we can see we have desktop documents downloads music pictures public and

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many more by many more I'm into more.

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So if you for example wanted to list all of the files that are in the slash through directory you would

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use it which you would do it with Alice.

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What else minus file a comment.

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What this does is basically it will print out same day.

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Also these sub directories but it will also print out the hidden files and hidden sub directories and

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we can see right here it's printed out more files than this command right here.

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So as you can see all of these files and start with DOT are not being seen in the Alice comment.

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So if you want to give to take a wide view on all of the current files into this slash root directory

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you can do it with Alice minus a leg comment.

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Now also one important comment is to clear screen so you don't see all of this all the time.

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You can do it with a simple command which basically just as it says just clears.

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So type here clear.

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And it should remove all of the commands that we ran previously and it should give us a new and freshly

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opened terminal for example let's say you wanted to go to the desktop directory which is up directory

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of slash route.

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You can do that with a simple two letter command which is basically just see the desktop.

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This C.D. stands for a change directory and it will basically just put us in the desktop directory right

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now.

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As you can see right here the terminal is now located in the slash desktop directory.

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If we type here the p WD once again it will show us that now our current directory is slash root slash

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desktop.

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Now let's say for example you wanted to create a file in the desktop directory.

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You can do that in with the simple command which is touch and let's say file want the file that the

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stay for example.

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And now if we type here our S which will list all the files in this directory it will just print out

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the file that the axes we created that file text the.

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The extent with this command right here.

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So basically touch command create files and the let's say right now we for example wanted to remove

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this file.

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Now how do we remove the file we remove it with also a two letter command which is just our plan stands

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for remote.

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So we just type here remove file dot DSD and if we type you Alice once again which will list all the

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parts in the directory we'll see nothing because the only file that was there was the file that we previously

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created and then after deleted it.

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So let's cover that once again.

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We are currently in the slash through slash desktop directory and if we want to create the file we basically

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type touch files of the estate.

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Now this doesn't have to be filed that Steve can be anything.

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That's the key.

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It can just basically be anything.

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So for example it doesn't even have to be dot the exceed so much anything.

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And if we type unless once again we can see there is a file called anything.

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So let's do again let's remove it.

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We type here are anything.

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And if we type unless one.

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So again it won't be there anymore.

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Now we covered how to make files right now.

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But let's say we for example wanted to create a sub directory in this nested directory so to make a

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directory which is basically just a folder you want to type the command and K here which stands for.

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Make the rectory and then type here the directory name you want to make.

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So for example let's say we want to make directory called Kelly it will and let's say we list right

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here.

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The current test the directory.

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It will have a sub directory called Kelly that we just created.

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Now you might notice that the sub directories are different color than the basic file so let's make

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our file one again file one sixty.

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And let's list again you can see that the file one that the T is white while the sub the rectory is

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blue.

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So files will be different color than sub directories you should know that.

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Well it's not that important but you will get used to it in time so let's delete the file once again

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with the R.M. comment.

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Now to delete the sub directory you want to use the same crime comment which is file one which is on

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the Mark Kelly but you will notice that if we wanted to leave it there Kelly it will says cannot remove

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Kelly is a directory.

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Now in order for us to delete the directory we need to add a minus r at the end of comment to just type

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here again.

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KELLY And just add here minus r and as you can see the command work properly and is free type S again

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it won't be there there is no Kelly directory anymore so let's clear our screen with the clear command.

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And right now I just want to tell you before I cut this editorial right here that the comment R N minus

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r is very dangerous.

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Now you might be asking why.

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Well basically I'll show you why.

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For example.

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Let's create a directory called filed for example.

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Here we can see with the allies command it's right there and we want to change our current directory

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into the file directory.

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We do it like this and you can see that our current path right now is slash desktop slash file where

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in the directory that we previously created.

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So now let's say that we create three files right here file one such file to touch file three and if

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we type Ellis here we can see that right now we have three files right here.

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Now why is the arm mind the Sarah comments so dangerous.

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Well if you're a root account and you just type here are a minus are part of me if you yes R.M. you

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will notice that the R.M. the star and then minus your comment deleted everything.

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So now you might be wondering so what which is deleted all three files in one command which basically

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this star right here is referring to all the files in the sub directorate.

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So if you type your disk command which is R.M. star minus r it will delete all of the files in the current

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directory.

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So as you can see we don't have any file left.

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Now the reason this is so dangerous is because if we go to the root directory and type the same command

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our REM star minus r it will basically delete all the files on the Linux system which will make your

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this machine crash and not work anymore.

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Now I'm not sure if they updated it and if it is for some permissions or not permissions but confirmation

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in order to run this comment but we will not tested right here because you will be deleting all of the

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files all of the files in this system so for this part want to drill that would be it will cover other

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comments in the tutorial with the basic Linux commands and I hope I see you there by.