Introduction
Did you know Linux is the most popular operating system in the world? It is! For servers and supercomputers. The millions of server computers hosting the websites we visit are more than likely running a version of Linux. In this post, we'll learn what Linux is and where it comes from, vocabulary, and commands you need to start navigating this exciting platform.
What is Linux?
Linux is an operating system, just like Windows or Apple's mac OS. Operating systems are collection of software that manage the different devices and applications in your computer. These bits of software take care of processes like shutting down your computer, booting it up, and giving your programs an interface to interact with devices like your keyboard and mouse.
Learning to use a Linux system is a great opportunity to get familiar with the command line, the most explicit way to communicate with your machine. Additionally, as you experiment with different projects, you will start to learn about repositories, package management, file permissions, user management, and much more. Package management and repositories are concepts you might already be familiar with if you have any experience using npm and GitHub.
Why is Linux so Popular?
Linux distinguishes itself in the world of enterprise computing, big data, and science (think supercomputers!). Why?
- Linux is free. Free in multiple ways, you don't need to pay to use Linux and you're free to view, edit, and distribute the source code. When you buy a computer with Windows or macOS, the cost of creating and maintaining these operating systems is included in the price.
- Linux is flexible. Linux is used in a lot of different types of computers. Think smart toasters and refrigerators, other IoT devices, internet routers, Android smartphones, the list goes on and on. You can probably install Linux on your laptop or desktop today and be up and running with little set up! More on this at the end. This flexibility is possible because a Linux operating system is designed to be the sum of many different tools that do one job and do it well. You could piece together a version of Linux that works for your device and is optimized for your needs.
The Unix Philosophy
Linux is a 'Unix-like' operating system, meaning much of it is derived from the Unix operating system and generally follows Unix's design principles. An ideal Unix program is simple, modular, and extensible. Unix programs do a few tasks really well and are designed to work well with other programs without depending on too many others. The system is made strong by the collaboration of the programs that compose it, not because the programs themselves are super powerful.
My favorite thing about Linux is that everything is a file somewhere in the system. Those commands and programs you run in the terminal? Files. The icons in your desktop that let you quickly open your favorite apps? Files. What about the repositories your system checks for application updates? Written in a file! All of which you can mess around with. The transparency! The power! Its beautiful. Imagine one day set up your own Linux installation with everything you want, and nothing that you don't, while having full autonomy over your system... Pretty cool, right?
These principles really speak to Linux's flexibility. No wonder it's used in for so many applications!
Everything is a File, Here is Where They Live
I want to show you a typical system tree, or file system hierarchy in a Linux installation. Read more about tree-like data structures in my other post! If you're following along in your own Linux system, note that you may have additional or fewer directories. If you want to learn more these directories (folders) in detail, run man hier in your Linux terminal and read away! Personally, I keep my search engine of choice nearby to look up the many words I don't know the meaning of.
/ this is the root directory (folder), the root of the tree (yes, the data structure 😄)
/bin contains binaries, executable programs the system needs to boot
/boot contains the kernel and files needed while the machine boots
/dev contains device nodes, instructions/interfaces to use with physical devices connected to machine
/etc contains system-wide configuration files (pronounced etsy). Big software packages like gtk, python, and X11 store configuration files here as well.
/home contains directories for system users (each user's Downloads, Pictures, etc.)
/lib contains libraries shared by core programs necessary to boot the machine
/lost+found contains data misplaced during a system crash or as a result of drive errors
/media contains mount points for media devices like USBs, CDs, and DVDs.
/mnt is a mount point for a temporary file system (like the one you might use to build your installation)
/opt contains additional packages for programs. In my machine, Google Chrome and the Minecraft Launcher keep files here.
/proc contains files related to the kernel and running processes
/tmp contains temporary files that may be created while executing a program
/usr contains a secondary, read-only system tree for sharing with some programs or to be mounted on other Linux systems. Many of the directories above exist here containing additional files.
/var contains files that vary in size at different times like logs and backups
If you use Linux frequently, at one point or another you'll find that you need to edit or write files in some odd directory. I hope knowing what these names generally refer to can help you out!
Command Line Basics
Earlier I said 'the most explicit way you can communicate with your Linux machine is the command line' and I meant it. Let's learn some basic command line or terminal commands that will allow you to start familiarizing yourself with your system. If you currently develop with a graphical user interface you may find that doing things from the terminal is faster and safer (ish).
There is a program between you and the terminal called the shell. A shell is a program that interprets text commands and sends them to your operating system to execute. The most common shell program is called Bash, which comes included in most Linux installations. For macOS users, Apple recently switched the shell program to zsh. macOS is actually a Unix-like operating system as well. You too can change your shell!
The Structure of a Terminal Command
I won't share too many commands in this post, its long enough already and learning patterns is more important. Generally, terminal commands follow a very similar and predictable structure:
program_name [--optional flags] [optional arguments]
Flags can come after arguments and are often shortened to just one letter and one dash, e.g. -f. Flags are options that change the way a program behaves. -h or --help are common flags that will tell a program you want to see which flags are available to you.
Arguments are often files but can be strings and numbers too.
You can call a program from any directory in your system and you can use a file from any directory in your system as an argument. You can do this because to name a file you can use a relative or absolute path. Relative paths are relative to your current directory, which you can refer to with .. Absolute paths start at the root of the system / and name every directory to get to the desired file.
Navigation
pwdprints the directory you're currently in (print working directory)cdchanges the directory to your specified argument. If you provide no arguments it will by default take you to your user's directory, which you can refer to in paths with~..and..represent your current and parent directories respectively and are also valid arguments.lslists the files in the directory you specify as an argument, which by default is.. The-aflag comes in handy for seeing hidden files. You can hide files by starting their name with a., e.g..gitignoreto reduce clutter.
ls -a ~/Documents
File Manipulation
-
mvmoves a file or directory to your specified directory.
mv fun-letter.text ~/Documents/letters/
You can also use mv to rename files and directories:
mv fun-letter.txt hilarious-letter.txt
Like moving it to itself with a new name!
cpmakes a copy of a file in a specified directory. Use the-rflag to copy directories, and you can rename files and directories withcpsimilarly to how we did it withmv.mkdirmakes new directories where the names are your arguments. You can also make directories inside directories that don't exist yet with the-pflag.
mkdir -p code/web-stuff/html notes
-
touchmakes new files where the names are your arguments.
You will soon find yourself wanting to do more complicated things, so read more on these commands and keep a cheat-sheet 😉.
Linux for Everyday Use
I won't say 2020 is going to be the year for Linux in the desktop, but I will share that there are many Linux distributions ready to go out of the box and with simple installation methods. If you are attracted to the power of the shell, are concerned about privacy using other operating systems, or you just like hacking around, Linux might be for you. As a developer this is also a great platform because its made with other developers in mind. Distributions, versions of Linux like Ubuntu, Linux Mint, and Fedora can get you up and running quickly. These 'distros' are accompanied by huge communities full of people willing to help. Just remember to back up any important files!
Thanks for reading! I appreciate any comments and feedback :)
Latest comments (26)
Free as in freedom. I love that.
with Microsoft pushing Linux into Windows OS via WSL, my opinion is that Linux is losing the Desktop segment.
Is it? I always though it was pronounced et cetera... like the Latin phrase used in English?
Oh Pleaseeee!!!!
Am I the only one seeing this post as complete mislead!!? First of all, LINUX is not an operating system, it is just a kernel(a teeny-tiny but very important part) of an OS. GNU/LINUX is the complete Operating System suite. GNU(most of the OS) + Linux (part of the OS, Kernal)
Do give credit to GNU as well, which worked 95% on the so called Operating System you are talking about.
gnu.org/gnu/linux-and-gnu.en.html
Yes it would have been good to point out GNU (and things like desktop managers, Gnome, KDE etc) ... but talking about giving credit, Linus Torvalds isn't even being mentioned in the article! For the rest, in my opinion this article is a very nice overview for the Linux n00b :-)
Well, every GNU thing can be easily replaced, while you can't easily replace the linux kernel itself for anything better. Also, one could argue that even the Desktop Environment plays a bigger role than the GNU software.
I completely agree with the adaptability and different flavours. But we should not forget the effort of GNU team put in making a FOSS Operating System against all proprietary giants at that time. And am not dis-honouring the contribution of Linus Torvalds as well, he has done a tremendous job. What we should not do is praise or give credit only to Linux or Torvalds. Please give credits to GNU as well.
When Mr. Torvalds made his kernel FOSS, there was a similar project called HURD going on with GNU to replace Unix kernel.
What I actually mean is , people who write/speak about Linux Operating System and don't know/mention about GNU, they should revise their knowledge base!!
HURD was, and still is, not really useful for anything.
I don't think GNU deserves any other mention that what it already has in the license files and some package names.
Even in the link you posted they base relevance on line of code amount. If we go by that metric, then even a web browser deserves way more credits than GNU itself due to their higher LoC amont, but we don't see anyone calling their systems Chrome/Linux or Firefox/BSD.
I do think GNU deserves a mention.
If Linux was solely developed, and not combined with an OS like suite(which was already present) no one would have used it. Or if GNU tried (still trying to write a completely Free kernel) it would have been ages to see a Free and Open Source Operating System. By the time we all would have became slaves to big tech conglomerate.
A complete FOSS OS is true now because of both GNU and Linux so they does deserve mentioning.
Hey E,
Loved: 'man hier'. That was totally new to me. And I thought I had been using Linux a while. ;)
And cell phones! Android is based on linux kernel.
excellent (and practical) article!
The only drawback in linux is that you can’t play popular games on it😓, thats why i have windows along with linux
Try this if you haven't yet: github.com/ValveSoftware/Proton.
The best part of this is that you just have to check a checkbox labelled "Enable SteamPlay for all titles" under Settings after which Steam restarts and then you have access to thousands of Windows games on your Linux machine. Since Valve introduced Proton, things have been turned around in the world of Linux gaming.
As we're discussing games on Linux, I could'nt skip mentioning gamingonlinux.com.
Which games have you been unable to play, specifically?
League of legends
Starcraft 2
I can't speak to League of Legends, because I don't play it. On a quick search, it looks like a new "anticheat" method that Riot is introducing is fundamentally incompatible with Linux, because it's kernel level, though 😠 . Honestly, even as a Windows gamer, I'd push back heavily on this new method they're looking to implement, because that's draconian as hell. It is, for all intents and purposes, a rootkit with more privileges than the system administrator account. and it runs even when the game is not, and is not removed when you uninstall their games (instead, you have to uninstall it separately).
Starcraft 3 doesn't exist, but Starcraft 2 plays just fine.
One thing I've noticed over the years is that Linux is the canary in the gaming coal mine, especially at this point. Pretty much any game that isn't actively dis-supported (ie - support and compatibility actively removed) and is simply not written specifically for Linux but uses fairly standard libraries and methods and such, work out of the box. Hell, I played Borderlands 3 the week it launched on Steam without much problem.
So when a game doesn't work on Linux, even if it's not officially supported, 9 times out of 10, it's because the company actively did something to break it. Very often lately, it's been "anti-cheat" software that's overly invasive -- and considering how much flak Acti-Blizz got for Warden being invasive when they first launched it and all of the Acti-Blizz games work just fine on Linux, and Warden pales in comparison to things like Riot's new one, that's saying a ton.
In my opinion, even if you're a die-hard Windows gamer who couldn't possibly care less about the state of gaming on Linux, it's worth seeing what games cannot run at all under Linux, because they're few and far enough between these days that there's a very good chance it's a dead canary and there's something that the publisher is doing that is ethically sketchy.
You can play games, if some is not supported is not Linux's fault but it's maker
Yes i know that, unfortunately not a few companies are doing this 😓
Thanks! Such an impressive and visionary work to code an OS 20yrs ago and don't have to change anything all these years.
My favorite learning Linux project is Linux From Scratch - learned a tone 15yrs ago.
Such a cute ... guy!
I've been using Linux since 1998, and nothing to say to your post but "good work!" I wish I'd had have this kind of document 22 years ago :D
Nicely done, thanks!
But you have to, we have been saying it for a decade, is tradition!.
For a decade? They were saying that already when I started using Linux in the late 1990s/early 2000s.
But that was nonsense, because clearly THIS is the year of the Linux desktop.
And those where really optimistic, when I used Mandrake 9.1 many years ago, almost none knew about Linux, half of the HW didn't worked, no big vendors sold machines with it and most of the distros, if not all, couldn't even play mp3.
I'm not even sure I would like the year of the Linux desktop to come, most users don't care about freedom, customization. good design or privacy. What would happen if all Windows users came to our side?, what would happen when 90% of now Linux users stop caring about those attributes?, things like when Ubuntu got bashed because it got Amazon ads in their main menu, wouldn't happen anymore, blobs would start to proliferate, we would have scenarios like Nvidia, where the FOSS alternative is almost unusable but nobody cares because the blob just works, everything would be chaos and horror and fire would fall from the skies!, or not, who knows. Hopefully we'll have Slackware with its awesome shitty website, the mighty Gentoo and all the Linux craziness.
As Ian Malcolm said, "Weirdness cannot be contained. Wirdness breaks free. Weirdness... finds a way", long live FOSS
Great intro to Linux!