This course provides an overview of Kali Linux and some of its main components and features. We'll also take a look at Linux in general including how it looks, how to use it, how to use the command line, how to change the settings, and more. We recommend taking this course as part of the Web Penetration Testing & Bug Bounty Hunting learning path.
This course is intended for anyone who wants to learn the basics of Kali Linux, with a view to becoming an ethical hacker and/or a bug bounty hunter.
To get the most out of this course, it would be beneficial to already have some experience with Linux.
Hi, within this lecture, we're going to start seeing the basic Linux commands. So, what we're going to do, we're going to run the terminal. So, within this terminal you might see your user name as a different thing rather than kali. So, if you have installed the ISO, you have already determined your own user name. If you're using the OVA created for this course, you may see this as route and it doesn't matter. We're going to see what difference can it make in the upcoming lectures. But right now you just have to worry about what's coming next. So, you don't have to worry about this at all. So, you have a different user name, maybe you have the same user name, it really doesn't matter. What matters is that we need to understand what this terminal does. So, within this terminal we write commands and it actually gets executed by kali Linux and in fact, we have seen this when I showed you how to change the keyboard.
So, what we're going to do next is to open this file manager. So, if you open the folder, you can see that whether your user name is kali or something else you can see all these documents, downloads, desktop, file system, and everything. So, what we're going to do next is to learn how to navigate inside of the terminal so we can execute comments in any of these folders and it can make a difference. So, first of all we need to understand how to navigate. Right now we are in some folder, we are in some place inside of our file manager and we don't know where. So, in order to find out, we need to write some comments, we need to execute some comments and check the output. And then we can navigate through as if we are clicking, double clicking on any of these going into the documents, creating a folder here. Let me do that. Let me create a folder, but not from here maybe from the terminal.
Let me show you what I mean. I'm inside of kali right now, and I'm writing pwd. It stands for print working directory. So, it will show you where we are currently as it turns out that I'm inside of home/kali folder. So, it's the same folder that I have seen, that I opened the file manager before because I'm inside of the kali user. And again, if you're inside of some other user then you should be seeing that. And it really doesn't matter where you are right now, because we're going to see how to navigate in a minute. So, over here, what I'm going to do, I'm going to try and see what folders and files are there inside of the home and kali. So, it turns out I'm inside of the kali folder. So, maybe I want to go into some of the folders, like documents and downloads and stuff. By the way if you come over here to file preferences, you can change the font, you can change the appearances, so my size is 20 right now. If you want you can make it bigger, you can make it smaller. I'm using it this big so that you can see it in a better way. But you can change it in a way that you want.
Anyway so we have printed out the working directory. And again, I wonder what's inside of it. So, I can run this ls. It's listing. It lists the folders and files available in the current folder. If I open that folder, you will actually see that desktop documents, downloads, and stuff are actually inside of this kali folder. So, I see exactly those folders. If I want to, I can double click into any of those. I can change my folder for example into the documents and I can see what's inside of that as well. The command to do that is cd, and cd stands for change directory and you have to make sure that you're writing exactly as it is like upper case D and something like that. So, you should exactly write like the cd space documents or cd space downloads. And once I execute that, I'm inside of the documents right now. Now, I have double clicked. So it's exactly like double clicking. Now if I run ls over here as you can see, I got nothing back because there isn't anything inside of the documents. If there was I would have seen that.
Great, now I'm going to right click and create a folder over here for example, I'm going to create a test folder. And once I do that, I can go back to the terminal and run ls one more time to see test folder actually exists. Right now I'm getting test because it's there. Of course, I could have created this test from here as well. We're going to see it, don't worry. But the idea we're here is that you can see the available files and folders and you can interact with them using the terminal. And obviously we don't have to go over the file manager and right click and create folder anytime we need to create a folder or create a document. We can do that with the terminal as well. Right now I'm inside of the documents and assume that I want to create a test folder. If I'm sure that I'm inside of the documents, inside of my terminal, I mean, I can run this command mkdir, so mkdir it stands for making directory. So, for example, if I write this, mkdir test2 and if I write ls, I can see that test and test2 is actually over there. As you can see, it's actually created the test2 folder inside of the documents.
And the idea of the navigation between the folders derives from this because once I, by the way, if you write clear, it just clears the screen. Once I created that folder, it actually has been created inside of the documents. Right now, if I write ls I can see it. If I want to, I can go into that folder as well writing cd test2. Right now, I'm inside of the documents and test2 folder. If I create any file or if I create any folder, I can just do it in the test2. And if I write this cd .. it will just take me to the previous folder which is the documents in this case. It's exactly like clicking on the back button over here. So, of course you can use the cd command and ls command in order to navigate throughout the terminal. So, for example you can go back to the user, the home kali folder. You can go to the downloads, you can go to the desktop, you can create folders, you can create files if you want. So, depending on where you are, it may produce some different behavior. For example, if you create a folder inside of desktop, it will appear in the desktop, not in the document. So, that is why it's important for us to learn about this navigation first.
So, right now I'm inside of the documents and if I write ls I can see the folders. So, there is test and test2. So, assume that I want to create a file. So the comment for that is touch. So, if you write anything over here after the touch, it will be created. It can be a Python file, Java file, txt file, jpg file, whatever you may want to think of. It doesn't create a folder, it creates a file for you. And obviously, we can use this to create some, maybe, I don't know text files to have some notes inside of it. For example, notes.txt. And when I execute this, this notes.txt is actually created inside of the documents folder as you can see. Right now I can double click on it, I can write anything inside of it and by the way before double clicking, maybe you may want to right click it and just select the thing that you may want to open this with, but don't worry about the editors like mouse pad Vim. I'm just going to show you a better way to do that. So, don't worry about opening and writing something inside of it. We're going to use something called nano in order to do that for the upcoming lectures.
Right now we're just seeing how to navigate through. So, assume that we have created this note.txt. Maybe I want to move that, maybe I want to delete that, maybe I want to see the difference between those and the folders. So, if I write ls, as you can see, note.txt is written in white and these test are written in blue. Of course, it depends on the team, it depends on the colors, but they are shown in different colors, so that we can understand whether this is like a file and folder. And if I go to cd.. if I write ls, as you can see everything is shown in blue right now, which makes me think that is everything is folder right now, so I can go back and I can see that if I write ls the kali is again a folder. There isn't any file inside over here. So, this home folder is actually the folder for different users. Of course we can have multiple users when we use the Linux. And right now I'm seeing kali, maybe you're seeing something else. But it doesn't matter right now you know how to navigate between them. You can write cd kali or cd, whether you see it over here and then you can come to that folder and you can run Ls to see the content of it. So, make sure you run pwd before you do anything else so that you can understand where you are. And if you want you can run mkdir, touch, Ls, cd .. and so all of this stuff will enable you to navigate through the terminal. But again, maybe I want to delete them, maybe I want to move them. And in order to do that, we need to learn all those commands as well. That's exactly what we're going to do within the next lecture.
Atil is an instructor at Bogazici University, where he graduated back in 2010. He is also co-founder of Academy Club, which provides training, and Pera Games, which operates in the mobile gaming industry.