What is the purpose linux

What is Linux?

From smartphones to cars, supercomputers and home appliances, home desktops to enterprise servers, the Linux operating system is everywhere.

Linux has been around since the mid-1990s and has since reached a user-base that spans the globe. Linux is actually everywhere: It?s in your phones, your thermostats, in your cars, refrigerators, Roku devices, and televisions. It also runs most of the Internet, all of the world’s top 500 supercomputers, and the world’s stock exchanges.

But besides being the platform of choice to run desktops, servers, and embedded systems across the globe, Linux is one of the most reliable, secure and worry-free operating systems available.

Here is all the information you need to get up to speed on the Linux platform.

What is Linux?

Just like Windows, iOS, and Mac OS, Linux is an operating system. In fact, one of the most popular platforms on the planet, Android, is powered by the Linux operating system. An operating system is software that manages all of the hardware resources associated with your desktop or laptop. To put it simply, the operating system manages the communication between your software and your hardware. Without the operating system (OS), the software wouldn?t function.

The Linux operating system comprises several different pieces:

1. Bootloader – The software that manages the boot process of your computer. For most users, this will simply be a splash screen that pops up and eventually goes away to boot into the operating system.
2. Kernel – This is the one piece of the whole that is actually called ?Linux?. The kernel is the core of the system and manages the CPU, memory, and peripheral devices. The kernel is the lowest level of the OS.
3. Init system – This is a sub-system that bootstraps the user space and is charged with controlling daemons. One of the most widely used init systems is systemd? which also happens to be one of the most controversial. It is the init system that manages the boot process, once the initial booting is handed over from the bootloader (i.e., GRUB or GRand Unified Bootloader).
4. Daemons – These are background services (printing, sound, scheduling, etc.) that either start up during boot or after you log into the desktop.
5. Graphical server – This is the sub-system that displays the graphics on your monitor. It is commonly referred to as the X server or just X.
6. Desktop environment – This is the piece that the users actually interact with. There are many desktop environments to choose from (GNOME, Cinnamon, Mate, Pantheon, Enlightenment, KDE, Xfce, etc.). Each desktop environment includes built-in applications (such as file managers, configuration tools, web browsers, and games).
7. Applications – Desktop environments do not offer the full array of apps. Just like Windows and macOS, Linux offers thousands upon thousands of high-quality software titles that can be easily found and installed. Most modern Linux distributions (more on this below) include App Store-like tools that centralize and simplify application installation. For example, Ubuntu Linux has the Ubuntu Software Center (a rebrand of GNOME Software? Figure 1) which allows you to quickly search among the thousands of apps and install them from one centralized location.

Why use Linux?

This is the one question that most people ask. Why bother learning a completely different computing environment, when the operating system that ships with most desktops, laptops, and servers works just fine?

To answer that question, I would pose another question. Does that operating system you?re currently using really work ?just fine?? Or, do you find yourself battling obstacles like viruses, malware, slow downs, crashes, costly repairs, and licensing fees?
If you struggle with the above, Linux might be the perfect platform for you. Linux has evolved into one of the most reliable computer ecosystems on the planet. Combine that reliability with zero cost of entry and you have the perfect solution for a desktop platform.

That’s right, zero cost of entry… as in free. You can install Linux on as many computers as you like without paying a cent for software or server licensing.

Let’s take a look at the cost of a Linux server in comparison to Windows Server 2016. The price of the Windows Server 2016 Standard edition is $882.00 USD (purchased directly from Microsoft). That doesn’t include Client Access License (CALs) and licenses for other software you may need to run (such as a database, a web server, mail server, etc.). For example, a single user CAL, for Windows Server 2016, costs $38.00. If you need to add 10 users, for example, that’s $388.00 more dollars for server software licensing. With the Linux server, it?s all free and easy to install. In fact, installing a full-blown web server (that includes a database server), is just a few clicks or commands away (take a look at ?Easy LAMP Server Installation? to get an idea how simple it can be).

If zero cost isn’t enough to win you over? what about having an operating system that will work, trouble free, for as long as you use it? I’ve used Linux for nearly 20 years (as both a desktop and server platform) and have not had any issues with ransomware, malware, or viruses. Linux is generally far less vulnerable to such attacks. As for server reboots, they’re only necessary if the kernel is updated. It is not out of the ordinary for a Linux server to go years without being rebooted. If you follow the regular recommended updates, stability and dependability are practically assured.

Open source

Linux is also distributed under an open source license. Open source follows these key tenants:

• The freedom to run the program, for any purpose.
• The freedom to study how the program works, and change it to make it do what you wish.
• The freedom to redistribute copies so you can help your neighbor.
• The freedom to distribute copies of your modified versions to others.

These points are crucial to understanding the community that works together to create the Linux platform. Without a doubt, Linux is an operating system that is ?by the people, for the people?. These tenants are also a main factor in why many people choose Linux. It?s about freedom and freedom of use and freedom of choice.

What is a “distribution?”

Linux has a number of different versions to suit any type of user. From new users to hard-core users, you’ll find a “flavor” of Linux to match your needs. These versions are called distributions (or, in the short form, “distros”). Nearly every distribution of Linux can be downloaded for free, burned onto disk (or USB thumb drive), and installed (on as many machines as you like).

Popular Linux distributions include:

• LINUX MINT
• MANJARO
• DEBIAN
• UBUNTU
• ANTERGOS
• SOLUS
• FEDORA
• ELEMENTARY OS
• OPENSUSE

Each distribution has a different take on the desktop. Some opt for very modern user interfaces (such as GNOME and Elementary OS’s Pantheon), whereas others stick with a more traditional desktop environment (openSUSE uses KDE).

You can check out the top 100 distributions on the Distrowatch.

And don’t think the server has been left behind. For this arena, you can turn to:

• Red Hat Enterprise Linux
• Ubuntu Server
• Centos
• SUSE Enterprise Linux

Some of the above server distributions are free (such as Ubuntu Server and CentOS) and some have an associated price (such as Red Hat Enterprise Linux and SUSE Enterprise Linux). Those with an associated price also include support.

Which distribution is right for you?

Which distribution you use will depend on the answer to three simple questions:

• How skilled of a computer user are you?
• Do you prefer a modern or a standard desktop interface?
• Server or desktop?

If your computer skills are fairly basic, you’ll want to stick with a newbie-friendly distribution such as Linux Mint, Ubuntu (Figure 3), Elementary OS or Deepin. If your skill set extends into the above-average range, you could go with a distribution like Debian or Fedora. If, however, you’ve pretty much mastered the craft of computer and system administration, use a distribution like Gentoo. If you really want a challenge, you can build your very own Linux distribution, with the help of Linux From Scratch.

If you’re looking for a server-only distribution, you will also want to decide if you need a desktop interface, or if you want to do this via command-line only. The Ubuntu Server does not install a GUI interface. This means two things your server won’t be bogged down loading graphics and you’ll need to have a solid understanding of the Linux command line. However, you can install a GUI package on top of the Ubuntu Server with a single command like sudo apt-get install ubuntu-desktop. System administrators will also want to view a distribution with regards to features. Do you want a server-specific distribution that will offer you, out of the box, everything you need for your server? If so, CentOS might be the best choice. Or, do you want to take a desktop distribution and add the pieces as you need them? If so, Debian or Ubuntu Linux might serve you well.

Installing Linux

For many people, the idea of installing an operating system might seem like a very daunting task. Believe it or not, Linux offers one of the easiest installations of all operating systems. In fact, most versions of Linux offer what is called a Live distribution ? which means you run the operating system from either a CD/DVD or USB flash drive without making any changes to your hard drive. You get the full functionality without having to commit to the installation. Once you’ve tried it out, and decided you wanted to use it, you simply double-click the “Install” icon and walk through the simple installation wizard.

Typically, the installation wizards walk you through the process with the following steps (We’ll illustrate the installation of Ubuntu Linux):

• Preparation: Make sure your machine meets the requirements for installation. This also may ask you if you want to install third-party software (such as plugins for MP3 playback, video codecs, and more).
• Wireless setup (if necessary): If you are using a laptop (or machine with wireless), you’ll need to connect to the network, in order to download third-party software and updates.
• Hard drive allocation (Figure 4): This step allows you to select how you want the operating system to be installed. Are you going to install Linux alongside another operating system (called “dual booting”), use the entire hard drive, upgrade an existing Linux installation, or install over an existing version of Linux.
• Location: Select your location from the map.
• Keyboard layout: Select the keyboard for your system.
• User setup: Set up your username and password.

That’s it. Once the system has completed the installation, reboot and you’re ready to go. For a more in-depth guide to installing Linux, take a look at “How to Install and Try Linux the Absolutely Easiest and Safest Way” or download the Linux Foundation’s PDF guide for Linux installation.

Installing software on Linux

Just as the operating system itself is easy to install, so too are applications. Most modern Linux distributions include what most would consider an app store. This is a centralized location where software can be searched and installed. Ubuntu Linux (and many other distributions) rely on GNOME Software, Elementary OS has the AppCenter, Deepin has the Deepin Software Center, openSUSE has their AppStore, and some distributions rely on Synaptic.

Regardless of the name, each of these tools do the same thing? a central place to search for and install Linux software. Of course, these pieces of software depend upon the presence of a GUI. For GUI-less servers, you will have to depend upon the command-line interface for installation.

Let’s look at two different tools to illustrate how easy even the command line installation can be. Our examples are for Debian-based distributions and Fedora-based distributions. The Debian-based distros will use the apt-get tool for installing software and Fedora-based distros will require the use of the yum tool. Both work very similarly. We’ll illustrate using the apt-get command. Let’s say you want to install the wget tool (which is a handy tool used to download files from the command line). To install this using apt-get, the command would like like this:

The sudo command is added because you need super user privileges in order to install software. Similarly, to install the same software on a Fedora-based distribution, you would first su to the super user (literally issue the command su and enter the root password), and issue this command:

That’s all there is to installing software on a Linux machine. It’s not nearly as challenging as you might think. Still in doubt? Recall the Easy Lamp Server Installation from earlier? With a single command:

You can install a complete LAMP (Linux Apache MySQL PHP) server on either a server or desktop distribution. It really is that easy.

More resources

If you’re looking for one of the most reliable, secure, and dependable platforms for both the desktop and the server, look no further than one of the many Linux distributions. With Linux you can assure your desktops will be free of trouble, your servers up, and your support requests minimal.

For more information to help guide you through your lifetime with Linux, check out the following resources:

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What is Linux and Why There are 100’s of Linux Distributions?

Last updated October 29, 2020 By Abhishek Prakash 146 Comments

When you’re just starting out with Linux, it’s easy to get overwhelmed.

You probably know only Windows, but now you want to use Linux because you read that Linux is better than Windows as it’s more secure and you don’t have to buy a license to use Linux.

But then when you go about downloading and installing Linux, you learn that Linux is not a single entity. There’s Ubuntu, Fedora, Linux Mint, elementary and hundreds of other ‘Linux variants’. The trouble is that some of them look just like the others.

If that’s the case, why are there so many Linux operating systems? And then you also learn that Linux is just a kernel, not an operating system.

It gets messy. And you may feel like pulling your hair out. As someone with a receding hairline, I would like you to keep your own hair intact by explaining things in a way you can easily understand.

I’m going to use an analogy to explain why Linux is just a kernel, why there are hundreds of types of Linux and why, despite looking similar, they are different.

The explanation here may not be considered good enough for an answer in an exam or interview, but it should give you a better understanding of the topic.

Apologies in advance!

My analogy may not be entirely correct from a mechanical point of view. I’m not knowledgeable about engines, cars and other related mechanical stuff.
But in my experience, I’ve noticed that this analogy helps people clearly understand the concept of Linux and operating systems.
Also, I’ve used the term Linux OS instead of Linux distribution deliberately, so that newcomers don’t start wondering about distributions.

Linux is just a kernel

Linux is not an operating system, it’s just a kernel.

This statement is entirely true. But what does it mean? If you look at books, you’ll find the Linux kernel structure described like this:

Linux Kernel Structure

That is absolutely correct. However, let’s take a different approach. Think of operating systems as vehicles: any kind of vehicle, be it a motorbike, a car or a truck.

What is at the core of a vehicle? An engine.

Think of the kernel as the engine. It’s an essential part of the vehicle and you cannot use the vehicle without it.

But you cannot drive an engine, can you? You need a lot of other stuff to interact with the engine and drive the vehicle. You need wheels, steering, gears, a clutch, brakes and more to drive a vehicle on top of that engine.

Similarly, you cannot use a kernel on its own. You need lots of tools to interact with the kernel and use the operating system. These things could be a shell, commands, the graphical interface (also called desktop environment), etc.

This makes sense, right? Now that you understand this analogy, let’s take it further so that you understand the rest of it.

Windows and other operating systems have kernels too

The kernel is not something exclusive to Linux. You may not have realized, but Windows, macOS and other operating systems have a kernel underneath as well.
Microsoft Windows operating systems are based on the Windows NT kernel. Apple’s macOS is based on the XNU kernel.

Think of operating systems as vehicles

Think of Microsoft as an automobile company that makes a general-purpose car (the Windows operating system) that is hugely popular and dominates the car market. They use their own patented engine that no one else can use. But these ‘Microsoft cars’ do not offer any scope for customization. You cannot modify the engine on your own.

Now we come to the ‘Apple automobile’. They offer shiny-looking, luxury cars at an expensive price. If you have a problem, they have a premium support system where they might just replace the car.

Now comes Linux. Remember, Linux is just an engine (kernel). But this ‘Linux engine’ is not patented and thus anyone is free to modify and build cars (desktop operating systems), bikes (small embedded systems in your toys, TVs, etc.), trucks (servers) or jet-planes (supercomputers) on top of it. In the real world, no such engine exists, but accept it for the sake of this analogy.

• kernel = engine
• Linux kernel = specific type of engine
• desktop operating systems = cars
• server operating systems = heavy trucks
• embedded systems = motorbikes
• desktop environments = body of the vehicle along with interiors (dashboard etc.)
• themes and icons = paint job, rim job and other customizable features
• applications = accessories you use for a specific purpose (like the music system)

Why are there so many Linux OS/distributions? Why do some look similar?

Why there are so many cars? Because there are several vehicle manufacturers using the ‘Linux engine’ and each of them has many cars of different types and for different purposes.

Since the ‘Linux engine’ is free to use and modify, anyone can use it to build a vehicle on top of it.

This is why Ubuntu, Debian, Fedora, SUSE, Manjaro and many other Linux-based operating systems (also called Linux distributions or Linux distros) exist.

You might also have noticed that these Linux operating systems offer different variants but they look similar. I mean look at Fedora’s default GNOME version and Debian’s GNOME version. They do look the same, don’t they?

The component that provides the look and feel in a Linux OS is called the desktop environment. In our analogy here, you can think of it as a combination of the outer body and matching interiors. This is what provides the look and feel for your vehicle, does it not?

Based on the exterior, you can classify the cars into categories: sedan, SUV, hatchback, station wagon, convertible, minivan, van, compact car, 4×4, etc.

But each ‘type of car’ is not exclusive to a single automobile company. Ford offers SUVs, compact cars, vans. etc., and so do other companies like General Motors or Toyota.

Similarly, distributions (Linux OSes) like Fedora, Ubuntu, Debian, Manjaro, etc., also offer different variants in the form of GNOME, KDE, Cinnamon, MATE and other desktop environments.

Ford’s SUV may look similar to Toyota’s or Renault’s SUV. Fedora’s GNOME version may look similar to Manjaro or Debian’s GNOME version.

Some type of cars consume more fuel, some desktop environments need more RAM

You probably understand the ‘usefulness’ of different types of cars. Compact cars are good for driving in cities, vans are good for long trips with family, 4×4 are good for adventures in jungles and other rough terrain. A SUV may look good and feel comfortable to sit in, but it consumes more fuel than a compact car that might not be as comfortable.

Similarly, desktop environments (GNOME, MATE, KDE, Xfce etc) also serve a purpose other than just providing the looks for your Linux operating system.

GNOME provides a modern-looking desktop, but it consumes more RAM and thus requires that your computer has more than 4 GB of RAM. Xfce on the other hand may look old/vintage but it can run on systems with 1 GB of RAM.

Difference between getting desktop environments from the distribution and installing on your own

As you start using Linux, you’ll also come across opportunities to easily install other desktop environments on your current system.

Remember that Linux is a free world. You are free to modify the engine – customize the looks on your own – if you have the knowledge/experience or if you are an enthusiastic learner.

Think of it as like customizing cars. You may modify a Hundai i20 to look like a Suzuki Swift Dzire. But it might not be the same as using a Swift Dzire.

When you are inside the i20 modified to look like a Swiftz Dzire, you’ll find that it may not have the same experience from the inside. The dashboard is different, the seats are different. You may also notice that the exterior doesn’t fit the same on the i20’s body.

The same goes for switching desktop environments. You will find that you don’t have the same set of apps in Ubuntu that you would be getting in Mint Cinnamon. A few apps will look out of place. Not to mention that you may find a few things broken, such as a missing network manager indicator, etc.

Of course, you can put time, effort and skills to make the Hundai i20 look as much like a Swift Dzire as possible, but you may feel like getting a Suzuki Swift Dzire is a better idea in the first place.

This is the reason why installing Ubuntu MATE is better than installing Ubuntu (GNOME version) and then installing MATE desktop on it.

Linux operating systems also differ in the way they handle applications

Another major criterion by which the Linux operating systems differ from each other is package management.

Package management is basically how you get new software and updates for your system. It’s up to your Linux distribution/OS to provide the security and maintenance updates. Your Linux OS also provides the means of installing new software on your system.

Some Linux operating systems provide all the new software versions immediately after their release, while some take time to test them for your own good. Some Linux systems (like Ubuntu) provide an easier way of installing new software, while you may find it complicated in others (like Gentoo).

Staying with our analogy, consider installing software to be like adding accessories to your vehicle.

Suppose you have to install a music system in your car. You may have two options here. Your car could be designed in such a way that you just insert the music player, you hear a click sound and you know it’s installed. Alternatively, you might have to get a screwdriver and then fix the music player in place with screws.

Most people would prefer the hassle-free click-lock installing system. Some people might take the matter (and the screwdriver) into their own hands.

If an automobile company provides scope for installing lots of accessories in click-lock fashion in their cars, they will be preferred, won’t they?

This is why Linux distributions like Ubuntu have more users, because they have a huge collection of software that can be easily installed in matter of clicks.

Conclusion

Before I conclude this article, I’ll also like to talk about support, which plays a significant role in choosing a Linux OS. For your car, you would like to have an official service center or other garages that service the automobile brand you own, wouldn’t you? If the automobile company is popular, naturally it will have more and more garages providing services.

The same goes for Linux as well. For a popular Linux OS like Ubuntu, you have official forums for seeking support and a good number of other websites and forums providing troubleshooting tips to fix your problem.

Again, I know this is not a perfect analogy, but it helps understand things slightly better.

If you are completely new to Linux, did this article make things clear for you, or are you more confused than before?

If you already know Linux, how would you explain it to someone from a non-technical background?

Your suggestions and feedback are welcome.

Like what you read? Please share it with others.

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