Linux is one of the most stable, flexible, and secure operating systems in the world. Due to its constant kernel development and improvements by developers from all over the world, it has become the most popular operating system in the world. Linux is embraced by individual users, and government entities, and serves as the back-end operating system used by global giants such as NASA, Amazon, eBay, Facebook, Google, Microsoft, Apple, and many more.
In this lesson, I am going to walk you through the Introduction to Linux, its main components, its history and where is Linux used. So let’s get started.
What is Linux
Linux is not an operating system. Linux is the Kernel that is one important component and a part of an entire operating system. There are also other programs/utilities that are used in an operating system. Many users have misunderstood and considered Linux to be an operating system. Whereas the fact is that Linux Kernel is the program in the operating system that allocates the hardware resources to other programs that you run.
In its abstract form, an Operating System consists of Kernel and Utilities.
Operating System = Kernel + Utilities
Kernel is the core component of any operating system with full system control. It enables the interaction between hardware and Applications. The kernel has the access to resources such as CPU, I/O, and other resources and it acts as a bridge between the user’s application and the resources of the system.
Utilities are the basic programs or commands that allow users to perform basic operations. In Linux, they are referred to as coreutils which is a package of commands such as cp, cat, touch, rm, etc…
Application is just a software program that we can install in Linux as we do in Windows OS. We may use either of the following methods to install software packages/applications in Linux:
- Method 1: Download the software package locally and then install it.
- Method 2: Installing software packages directly from the repository without downloading them. Linux uses well-maintained software repositories to distribute software packages. A software repository is a collection of installation packages. This method is easy to install applications on Linux OS.
Example: The following table shows a few popular operating systems along with their Kernels. Applications can be installed and used on a need basis.
|Windows 10||Windows NT||Firefox, Zoom, Microsoft Office …|
|Ubuntu Linux||Linux Kernel||Firefox, Zoom, OpenOffice …|
|Rocky Linux||Linux Kernel||Firefox, Zoom, OpenOffice …|
For more details, please read Linux Distributions.
Linux History and Timeline
What is GNU/Linux?
In its abstract form, an Operating System consists of Kernel and Utilities.
- Linux is the kernel component of the operating system.
- And many of the other utilities were taken from the GNU project.
They were two different projects. GNU didn’t have its own Kernel and the Linux kernel alone was not sufficient to form a fully working operating system. Therefore, combining the components of these two projects have rooted the term “GNU/Linux”.
Who Owns and Develops Linux
Unlike other operating systems, nobody owns Linux. Linus Torvalds used utilities/software programs from the GNU project to turn Linux into a fully functional OS. Therefore, he licensed Linux under the GNU General Public (GPL) License. GNU General Public (GPL) License allows anyone to use, modify, and distribute the source code. Linux is freely available to everyone because of its open-source licensing. You can use the code for any purpose, change the code to suit your needs and share the changes you made. If you contribute any code changes to Linux and it gets approved by the designated community, you may retain the copyright to that piece of code. LINUX is a registered trademark of Linus Torvalds. However, Linux would still be free and available to users with the improvement you contributed.
Where is Linux Used
- Linux is everywhere. Supercomputers, most of the servers on the internet, IOT devices, and many mission-critical devices rely on Linux being stable and secure. The trend to use Linux on personal computers has also dramatically increased over the period of years.
- The “TOP500 project” lists and ranks the 500 fastest supercomputers for which benchmark results are submitted. All of the supercomputers list under the TOP500 project use an OS based on Linux Kernel.
- Linux is the most popular operating system and is the LINGUA FRANCA of modern data centers.
- Linux is one of the most popular operating systems in the world that is embraced by individual users, government entities, and serves as the underlying operating system. It is used by global giants such as NASA, Amazon, eBay, Facebook, Google, Microsoft, IBM, GitHub, Netflix, Apple, and many more.
- With the advent and adaption of technologies (SDN & NFV) in enterprises, Cloud, and Service Provider environments, Linux has become a must-have skill for network engineers.
- Network Automation tools such as Ansible, Netmiko, NAPALM, and others are well-used and maintained on the Linux operating system.
- SDN controllers such as OpenDaylight, Open Network Operating System (ONOS), RYU Controller, and Cisco’s APIC-EM Controller run on Linux.
- All major networking vendors use Linux as their underlying operating system on their routing, switching, and security devices. Cisco, Juniper, VMware, F5, Arista, Ruggedcom, and Cumulus Networks are some examples of networking vendors that use Linux.
- Linux is mandatory for Cybersecurity Engineers and Certified Ethical Hackers to learn. Linux distributions such as Kali Linux, Parrot Security OS, BackBox, BlackArch, and many more are well-developed for penetration tools.
- Linux and the Cloud: Linux runs most of the public cloud workload. Every cloud provider such as Microsoft (Azure), Google (GCP), and Amazon (AWS) offers different Linux operating systems in their cloud. In addition, they also offer customized Linux images with additional tools installed to meet certain requirements.
This website, you are browsing, is also hosted on a Linux Server.
Linux in Embedded Systems
Embedded systems are simply hardware and software designed to have a particular function. These embedded systems can be operated independently for a specific task, or they can be part of other devices to help control these devices. These embedded systems are found in various industries such as IT, Automotive, Medical, Consumer electronics, and military. And all these embedded systems require embedded software. Linux is the best and most popular operating system for such embedded systems.
Two popular examples of embedded software are Android and Raspbian. Both are derived from Linux.
Android is an operating system developed by Google. Aneroid’s base is a modified version of the Linux kernel. Nowadays it is used on touchscreen devices, TVs, and Wristwatches, etc… Like Linux OS, Android is also freely available as Android Open-Source Project (AOSP).
Raspbian or Raspberry Pi OS is a Debian-based operating system for Raspberry Pi. Raspberry Pi is a small debit-card-sized computer that can be used as a desktop computer.
Similarly, many companies have come up with their own proprietary version of Linux to support their embedded systems. Other examples include Routers, switches, and Firewalls that use Linux as their base operating system.
Is Linux Difficult to Use
Absolutely Not. Linux is very much similar to other operating systems you may have used such as Windows, and macOS. Linux has a graphical interface and many applications that you can install. For instance, on your Linux operating system, you may use Mozilla Firefox, Google Chrome, Zoom, Adobe Reader, OpenOffice, etc… There might be some software that you are using in Windows or macOS but are not available in Linux. You may need to use their alternatives in Linux. This doesn’t make Linux difficult to learn.
- Linux is a free and open-source operating system. The code that is used to develop Linux is available to the public. If you are skilled enough, use the source code, change it, and tune it to meet your needs.
- Free Linux repositories offer thousands of tools and utilities that are alternatives to any proprietary paid software.
- In its abstract form, an Operating System consists of Kernel and Utilities. Kernel is the core component of any operating system with full system control. It enables the interaction between hardware and Applications. Utilities in an operating system, are the basic software or commands that allow users to perform basic operations.
- GNU/Linux = Linux Kernel developed by Linus Torvalds + Applications/utilities developed under GNU project.
- Linux is secure and is well known for its stability/reliability for both personal and enterprise use.
- Linux is used by all mission-critical projects, including but not limited to most servers on the internet, enterprises, Data centers, Cloud Providers, Service Providers, Super Computing, and many more.