Linux File System/Structure Explained!

most people who have used Linux have seen the root directory but not everybody understands what the directories are used for - a Windows user opening the file manager looks very much like opening the home folder in Windows and all looks very familiar you've got your documents your downloads your pictures your videos same thing that is until they explore up the tree looking for the C Drive where's Program Files where's the directory that Linux is installed in - how do you find anything let me explain I'll take a quick minute here for new Linux users coming from Windows Windows and Linux evolved in very different ways once upon a time there was a thing called ms-dos the disk operating system it was command-line only but you could still run programs games and WordPerfect but you didn't need Windows Windows was added to PCs and you can install it on top of DOS you would start up your computer and type in win to start Windows it used letters to assign drives with a and B being removable disks since early pcs only had floppy drives with the addition of hard drives the letter C became the letter for your internal disk additional discs were given the next available letter you could install things in Doss wherever you wanted to windows installed itself in his own directory called funny enough Windows later Microsoft changed how it booted by evolving their kernel to be less and less dependent on DOS and eventually allowed Windows to boot directly without dos at all Microsoft's file directory structure kind of stayed the same now Linux is different and so is its file structure it also doesn't install applications like Windows does starting with Windows 95 Microsoft created the Program Files directory which was the default installation directory for most applications for the most part Linux follows UNIX traditions which is why uses the forward slash instead of the back slash like Windows Linux also cares about capitalization so you can have things like this file file file file file file as you can see while they're all named file they all use different capitalization so Linux will allow this because they're technically not named exactly the same Mac users who have explored their hard drives might find Linux a little more familiar this is because Mac's also evolved from a UNIX ancestor more specifically BSD so let's have a look at the route and go over how all this work this layout for the most part is outlined in the filesystem hierarchy standard or FHS which defines the structure and layout and is maintained by the Linux Foundation I want a note here that not all distributions follow this some do their own special thing also several ways of structuring the folders has changed over the years but most of what follows still applies in most cases so let's go end-to-end starting with bin in being short for binaries these are the most basic binaries which is another word for programs or applications things like LS to list your directory cat to display the output of a file and other basic functions are stored here skipping ahead a little bit I also want to point out s bin these are system binaries that a system administrator would use and that a standard user wouldn't have access to without permission both of these folders contain the files that need to be accessible when running in single user mode as opposed to the usual multi-user mode single user mode is a special mode that boots you in as a root user to allow you to do system repairs and upgrades or testing networking is usually disabled in this mode because of security issues when you install a program in Linux it's typically not placed in these folders next is boot this is a folder you don't want to play around in it contains everything your OS needs to boot in other words your boot loaders live here next we have cd-rom which I'm going to skip because it's not in all distros and it's more of a legacy mounting point for your cd-rom so let's move on to dev this is where your devices live Linux again following UNIX has a standard where it was decided everything is a file here you'll find your hardware a disk for example would be dev slash SDA here and a partition on that disk would be for example dev SD a1 SD a2 and so on you can also find everything else here from your webcam to your keyboard this is typically an area that applications and drivers will access and is rarely something a user should be dabbling in so going back to root the next folder is etc' the name of this folder has been argued as standing for etc edit to configurations are stored however when I'm talking about configurations I'm talking about for things that are system-wide such as apt in this folder for example you would find the list of all your sources what repos your system connects to as well as its various settings so if you're looking for something that is a system-wide application and not a per user setting for example Libre Office would have settings in each user's folder and it wouldn't be system-wide because each user can have different settings and this brings me to the next folder which is home however I'm going to save this for the end because there's some things I want to discuss about it so we'll come back to it later next are the Lib folders this includes Lib Lib 32 and lips' 64 these are where the libraries are stored libraries are files that applications can use to perform various functions they're required by the binaries in bin and s bin for example moving on we have media and MNT or mount these directories are where you would find your other mounted drives it can be a floppy disk USB stick external hard drive network drive or even a second hard drive so if you're looking for that a B or D Drive this is where you want to be looking now this media folder wasn't always around it was typically just MNT and that's where you mounted your storage devices nowadays most distros automatically mount devices for you in the media directory so your USB stick that you inserted would be in media user name device name so why are there two directories well if you're mounting things manually use the MNT directory and leave the media directory to the OS to manage most distros and file managers such as Nautilus for example what I'm using here and dolphin and PC man FM will have something on the side here for example in Nautilus I can click other locations and here I can access my other devices if I had a USB stick plugged in right now it would show up here and I could simply click on it and access it next down the line is opt this is the optional folder which is usually where manually installed software from vendors resides though some software packages found in the repo can also find their way here VirtualBox guest additions is one example so here for example is a VPN software that I installed and the drivers for my brother printer slash scanner this is also where you can install software you've created yourself this folder is where I place all the applications I've written first I on Linux next we have prop rock is where you'll find pseudo files that contain information about system processes and resources for example every process will have a directory here which contains all kinds of information on that process an example I can show you here if I open the system monitor I can see Dasia due monitors process ID or hid is two three four four so if I navigate to proc two three four four which is the pit for the Dasia dupe monitor I can see all kinds of pseudo files here this is much like dev where they're not actually files on the system this is the kernel translating other information to appear as files so for example here I can open the status file and it'll show me all kinds of information on that process there's tons more in here but this isn't something you want to play in if you are a developer if you're writing applications this is very handy here you can also find information like for the CPU for example this will give you all kinds of information on the CPU and you can also do up time which will print out your uptime for your system next is root root is the root users home folder unlike a user's home folder it does not contain the typical directories inside and it does not reside in the home directory you can store files here if you wish but you need root permissions to access it the location of this directory also ensures that root always has access to its home folder in case you have the regular users home directory stored on another drive which you cannot access next is run this one's fairly new and different distros use it in slightly different ways it's a temp FS file system which means it runs in RAM this also means that everything in it is gone when the system's rebooted or shut down it's used for processes that start early in the boot procedure to store runtime information that they use to function we've already covered s bin so next down the line is snap this is a folder where snap packages are stored and are mainly used by Ubuntu snap packages are completely self-contained applications that run differently than regular packages and applications this will be covered in a future video on its own since it'll take more time to explain SRV this is the service directory where service data is stored it'll probably be empty for you but if you run a server such as a web server or FTP server you would store the files that will be accessed by external users here this allows for better security since it's at the root of the drive and it also allows you to easily mount this folder from another hard drive next down the line is sis the system folder has been around a long time it's a way to interact with the kernel one older example is writing to a file using VGA switcheroo and change settings on graphic cards in a hybrid system this directory is similar to the run directory and it's not physically written to the disk it's created every time the system boots up so you wouldn't store anything here and nothing gets installed here TMP is of course a temp or temporary directory this is where files are temporarily stored by applications that could be used during a session one example is if you're writing a document in a word processor it will regularly save a temporary copy of what you're writing here so that if the application crashes it can look here to see if there's a recent saved copy that you can recover this folder is usually emptied when you reboot the system on occasion you might find some files or directory that remain and could be stuck there because the system can't delete them this normally isn't a big deal unless there's hundreds of files or the files are taking a lot of disk space in which case you might want to log in as the root user in single user mode navigate to this folder and manually delete them moving on we have the USR folder this is the user application space where applications will be installed that are used by the user as opposed to the bin directory is used by the system and system administrator to perform maintenance it's also known as the UNIX system resource and any applications installed here are considered non-essential for basic system operation installed applications will reside in one of several places here such as user bin user s bin or local bin local Ben with their required library stored in local user local Lib or user Lib most programs that are installed from source code will end up in the local folders many larger programs will install themselves into user share any installed source code such as the kernel source and header files will go into the SRC directory this directory seems like a confusing mess at first and while the directory structure and what goes where is laid out in the FHS I mentioned earlier you'll still have to sometimes look in other places to find things someone making a certain application might not adhere to the standard and could just do what they want also some distros may treat these folders differently as well going back to root we have next var var is the variable directory it contains files and directories that are expected to grow in size for example var crash holds information about processes that have crashed var log contains log files for both the system and many different applications which will constantly grow in size as you use the system you'll also find other things in here like databases for mail and temporary storage for printer queues also known as the spool and finally we will come back to the home folder when you enter the home folder you'll see that each user has its own folder inside of it the home folder is where you store your personal files and documents like I said each user has their own home folder and each user can only access their own unless they use admin permissions some users mount the home folder on a different drive or different partition which allows you to reinstall your system and preserve your files the home folder also contains many different directories which store your application settings a hidden directory is simply one that starts with a period Linux hides these by default you can view them in the file manager by selecting show hidden files or by pressing ctrl H this is of course using Nautilus in gnome and some file managers might be different PC man FM is also press ctrl H to view hidden files if you're in the terminal and you list files it'll only show you what is not hidden unless you specify - a for all and now you can see all your hidden files these hidden directory store things like cache some applications like a browser used to store temporary files other applications might store thumbnails or information that will be used over and over repeatedly then you have folders like config and local which store individual application settings genie for example can be found in config so here's the genie folder any settings that I change in the genie options are saved here if I go back to the home folder you can see that some applications store their settings straight into the home folder like GIMP for example these hidden folders are also where your desktop settings are saved whether you use open blobs KDE gnome unity they all save their settings here such as what wallpaper you use what theme you use and so on you can even place your icons and themes in these folders so that you can have a custom look and easily save them for reuse these hidden folders are important if you want to backup your files and your settings I covered backups how to do them and where to store them in another video which I'll link in the corner of the screen and in the description below if you don't customize your system or you don't care to then you can simply backup all the folders you see here if you want to save all your settings then you might want to include all the hidden files as well so if you reinstall your system you simply log in and all your theming will already be done just like you left it you will have to reinstall your applications but once you install them the settings you set for them will already be in place and the applications will run just like they did before so as you can see if Linux is kind of similar to Mac but very different from Windows although it seems like a mess it's actually a more efficient way of doing things and allows much more sharing of common resources between packages when it comes to adding and removing software your distro will have a package manager that will handle all this for you package manager tracks where everything is going so that when you remove your package it takes all those files with it I hope you found this informative I did put quite a bit of work into preparing it and I'll have quite a bit of editing to do now so if you liked the video please click like and don't forget to subscribe by hitting that big red button and the bell to get notified of new videos most importantly if you found it useful please share it by clicking that share button and spread it out to your Twitter Facebook or whatever platform you use as always you can also follow me over on Twitter at Dorian dot slash and swing by my patreon page as well all the links are in the description thanks for watching and until next time bash on you

Channel: DorianDotSlash

Views: 4,018,552

Keywords: linux, explained, root, bin, etc, usr, home, linux folders, filesystem, file system, directory structure, file structure, linux file system, linux directory structure, linux file system explained, linux root folders explained, linux for beginners, linux tutorial for beginners, linux file system hierarchy, linux file system structure, linux explained, linux folders explained, linux directories explained, linux directories, linux folder structure, directories, folders, learn, learn linux

Id: HbgzrKJvDRw

Length: 15min 59sec (959 seconds)

Published: Fri May 18 2018