What is Linux?
Linux. It’s been around since the mid ‘90s, and has since reached a user-base that spans industries and continents. For those in the know, you understand that Linux is actually everywhere. It’s in your phones, in your cars, in your refrigerators, your Roku devices. It runs most of the Internet, the supercomputers making scientific breakthroughs, and the world\'s stock exchanges. But before Linux became the platform to run desktops, servers, and embedded systems across the globe, it was (and still is) one of the most reliable, secure, and worry-free operating systems available.
For those not in the know, worry not – here is all the information you need to get up to speed on the Linux platform.
What is Linux?
Just like Windows XP, Windows 7, Windows 8, and Mac OS X, Linux is an 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 (often referred to as the “OS”), the software wouldn’t function.
The OS is comprised of a number of pieces:
The 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.
The 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.
Daemons: These are background services (printing, sound, scheduling, etc) that either start up during boot, or after you log into the desktop.
The Shell: You’ve probably heard mention of the Linux command line. This is the shell – a command process that allows you to control the computer via commands typed into a text interface. This is what, at one time, scared people away from Linux the most (assuming they had to learn a seemingly archaic command line structure to make Linux work). This is no longer the case. With modern desktop Linux, there is no need to ever touch the command line.
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”.
Desktop Environment: This is the piece of the puzzle that the users actually interact with. There are many desktop environments to choose from (Unity, GNOME, Cinnamon, Enlightenment, KDE, XFCE, etc). Each desktop environment includes built-in applications (such as file managers, configuration tools, web browsers, games, etc).
Applications: Desktop environments do not offer the full array of apps. Just like Windows and Mac, Linux offers thousands upon thousands of high-quality software titles that can be easily found and installed. Most modern Linux distributions (more on this in a moment) include App Store-like tools that centralize and simplify application installation. For example: Ubuntu Linux has the Ubuntu Software Center (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 are you constantly battling viruses, malware, slow downs, crashes, costly repairs, and licensing fees?
If you struggle with the above, and want to free yourself from the constant fear of losing data or having to take your computer in for the “yearly clean up,” 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 (including costly Microsoft Client Access License – CALs).
Let’s take a look at the cost of a Linux server, in comparison to Windows Server 2012. The price of the Windows Server 2012 software alone can run up to $1,200.00 USD. That doesn’t include CALs, and licenses for other software you may need to run (such as a database, a web server, mail server, etc). 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 you’re a system administrator, working with Linux is a dream come true. No more daily babysitting servers. In fact, Linux is as close to “set it and forget it” as you will ever find. And, on the off chance, one service on the server requires restarting, re-configuring, upgrading, etc...most likely the rest of the server won’t be affected.
Be it the desktop or a server, 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 personally used Linux for nearly twenty years (as a desktop and server platform) and have not once had an issue with malware, viruses, or random computer slow-downs. It’s that stable. And server reboots? Only if the kernel is updated. It is not out of the ordinary for a Linux server to go years without being rebooted. That’s stability and dependability.
Linux is also distributed under an open source license. Open source follows the following key philosophies:
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.
The above are crucial to understanding the community that comes together to create the Linux platform. It is, without a doubt, an operating system that is “by the people, for the people”. These philosophies are also one of the main reasons a large percentage of people use Linux. It’s about freedom and freedom of choice.
What is a “distribution?"
Linux has a number of different versions to suit nearly 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).
The most popular Linux distributions are:
Each distribution has a different take on the desktop. Some opt for very modern user interfaces (such as Ubuntu’s Unity, above, and Deepin’s Deepin Desktop), whereas others stick with a more traditional desktop environment (openSUSE uses KDE). For an easy guide to Linux desktops check out How to Find the Best Linux Desktop for You.
You can check out the top 100 distributions on the Distrowatch site.
And don’t think the server has been left behind. For this arena, you can turn to:
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 upon 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, or Deepin. If you’re 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’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 (there is always an “however” with Linux), 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.
For new users, check out “The Best Linux Distribution for New Users”, to make the selection a much easier task.
For most, 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 (I’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 layout 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 has the Ubuntu Software Center, Deepin has the Deepin Software Center, some distributions rely on Synaptic, while others rely on GNOME Software.
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. I’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:
sudo apt-get install wget
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:
yum install wget
That’s it...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.
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 at a minimum.
If you’re looking for more resources to help guide you through your lifetime with Linux, check out the following resources:
Linux.com: Everything you need to know about Linux (news, how-tos, answers, forums, and more )
Linux.org: Everything about the Linux kernel (with plenty of beginner, intermediate, and adavanced tutorials)
Howtoforge: Linux tutorials
Linux Documentation Project: Plenty of documentation (some may be out of date)
Linux Knowledge Base and Tutorial: Plenty of tutorials.