What is Linux? History, Features & Popular Distributions – TrainWithSKY
Posted on: 26 Oct 2025 | By: SKY Team
Linux is one of the most powerful, secure, and widely used operating systems in the world. From servers and smartphones to embedded systems and supercomputers — Linux powers millions of devices globally. In this article, we'll explore what Linux is, its fascinating history, and its most popular distributions that dominate the tech landscape today.
What is Linux?
Linux is an open-source operating system based on UNIX principles. It manages hardware resources, runs software applications, and provides a command-line interface for advanced users. The core component, known as the Linux kernel, was created by Linus Torvalds in 1991.
- Type: Open-source and free
- Architecture: Multi-user, multitasking, and portable
- Interface: Command Line (CLI) and Graphical User Interface (GUI)
- Use Cases: Servers, desktops, IoT, cloud computing, cybersecurity, and more
A Brief History of Linux
The story of Linux began in 1991 when Linus Torvalds, a Finnish student, started developing a free UNIX-like kernel. He shared the source code publicly, allowing developers around the world to contribute. This collaborative effort quickly evolved into the Linux operating system we know today.
| Year | Milestone |
|---|---|
| 1991 | Linus Torvalds released the first Linux kernel (version 0.01). |
| 1992 | Linux adopted the GNU General Public License (GPL), making it open-source. |
| 1994 | Linux kernel 1.0 was released — stable and ready for public use. |
| 2000s | Major distributions like Ubuntu, Debian, and Red Hat gained popularity. |
| Today | Linux powers everything from Android phones to cloud servers and IoT devices. |
Core Features of Linux
- Open Source: The source code is free to view, modify, and distribute.
- Multiuser Environment: Multiple users can work simultaneously without interference.
- Security & Stability: Robust permissions and kernel security make it ideal for servers.
- Customizable: Every component — from GUI to shell — can be personalized.
- Lightweight: Efficient resource usage makes Linux perfect for both low-end and high-performance devices.
- Powerful CLI: Command-line tools give developers precise control and automation capability.
Popular Linux Distributions (Distros)
Linux distributions (or "distros") are customized versions of the Linux OS designed for specific needs — from general computing to enterprise servers.
| Distribution | Best For | Description |
|---|---|---|
| Ubuntu | Beginners & developers | User-friendly and widely supported; great for desktop and cloud environments. |
| Debian | Stability & servers | Known for reliability and large software repositories. |
| Fedora | Cutting-edge development | Red Hat–backed distro with the latest open-source innovations. |
| Arch Linux | Advanced users | Minimalistic, rolling release system that gives full control to the user. |
| CentOS / AlmaLinux | Enterprise servers | Stable and compatible with Red Hat Enterprise Linux (RHEL). |
Linux in Modern Computing
Linux is at the heart of modern technology infrastructure — from web servers and supercomputers to mobile devices and cloud platforms. Major companies like Google, Amazon, and IBM use Linux-based systems to power their global services.
- Cloud Platforms: AWS, Azure, and GCP offer Linux as their preferred OS.
- Mobile OS: Android is based on the Linux kernel.
- Cybersecurity: Tools like Kali Linux are built specifically for ethical hacking and penetration testing.
- Development: Most modern programming environments run smoothly on Linux.
Learn Linux with TrainWithSKY
Whether you're a beginner or a professional, mastering Linux can open doors to countless IT and DevOps opportunities. TrainWithSKY offers hands-on Linux Practice Quizzes that help you test your understanding of:
- Basic commands and shell scripting
- File management and permissions
- Networking and process control
- Package management and system monitoring
- Server setup and troubleshooting
Final Thoughts
Linux is more than an operating system — it's a global movement of open-source innovation. Understanding its structure, commands, and distributions gives you a competitive edge in IT, cloud computing, and cybersecurity. Start your Linux journey today with TrainWithSKY Linux Practice Tests and build real-world skills through interactive learning.