A Brief History of Linux

Before we explore the 7 powerful concepts of what is Linux, let’s take a quick look at how Linux came to be:

• 1969 — UNIX was created at Bell Labs by Ken Thompson and Dennis Ritchie
• 1983 — Richard Stallman launched the GNU Project to create a free UNIX-like OS
• 1991 — Linus Torvalds released the first version of the Linux kernel
• 1992 — Linux became free software under the GNU GPL license
• 1994 — First major Linux distribution (Red Hat) released
• 2004 — Ubuntu launched, making what is Linux accessible to everyday users
• 2008 — Android (built on Linux) launched, changing the smartphone world forever
• 2026 — Linux continues to dominate servers, cloud, IoT, and enterprise computing

7 Powerful Concepts of Linux

Concept 1: The Linux Kernel 🧠

When people ask what is Linux, the most accurate technical answer is: Linux is a kernel.

The kernel is the core part of any operating system. Think of the kernel like the engine of a car. You don’t see it directly, but everything the car does depends on the engine working properly. The Linux kernel manages:

• CPU — How programs use the processor
• Memory (RAM) — Allocating memory to running programs
• Devices — Communicating with hardware like keyboards, monitors, and storage
• File System — How files are stored and accessed
• Networking — Managing internet and network connections

The Linux kernel is developed by thousands of developers worldwide, including engineers from Google, Red Hat, Intel, and Microsoft. It is one of the largest collaborative software projects in history.

💡 Fun Fact: The Linux kernel has over 30 million lines of code and receives hundreds of updates every year!

Concept 2: Linux Distributions (Distros) 🐧

Here is something that confuses most beginners learning what is Linux: Linux itself is just the kernel. What most people call “Linux” is actually GNU/Linux — the Linux kernel combined with other software tools.

A Linux Distribution (Distro) is a complete operating system built using the Linux kernel, packaged with a desktop environment, applications, and tools.

Think of it this way: the Linux kernel is the raw engine, and a distro is the complete, ready-to-drive car.

There are hundreds of Linux distros available. Here are the most popular ones:

For beginners wondering what is Linux to start with — Ubuntu is highly recommended as it has the largest community, most tutorials, and the easiest installation process.

Concept 3: The Linux File System 📁

Another key part of understanding what is Linux is knowing how its file system works. The Linux file system is organized very differently from Windows.

In Windows, you have drives like C:\, D:\. In Linux, everything starts from a single root directory represented by / (forward slash).

Here is the basic Linux file system structure:

/                   ← Root directory (everything starts here)
├── /home           ← User's personal files (like Windows "Users" folder)
├── /root           ← Home directory for the root (admin) user
├── /bin            ← Essential programs and commands
├── /etc            ← System configuration files
├── /var            ← Variable data (logs, databases)
├── /tmp            ← Temporary files
├── /usr            ← User-installed programs
├── /opt            ← Optional third-party software
├── /dev            ← Device files (hardware)
└── /proc           ← System process information

Key differences in what is Linux file system vs Windows:

• In Linux, everything is a file — even hardware devices and processes are represented as files
• File names are case-sensitive (File.txt and file.txt are two different files)
• There are no drive letters — everything is under one root /

Concept 4: The Terminal and Command Line Interface (CLI) 💻

One of the most iconic aspects of what is Linux is its Terminal — a text-based interface where you type commands to control your computer.

While Linux does have graphical interfaces (GUI), many Linux operations are done through the Command Line Interface (CLI), which is faster, more powerful, and essential for server management.

Basic Linux Commands Every Beginner Should Know:

# Navigation
pwd                 # Show current directory
ls                  # List files and folders
ls -la              # List with details and hidden files
cd /home            # Change directory
cd ..               # Go one level up

# File Operations
touch file.txt      # Create a new file
mkdir myfolder      # Create a new directory
cp file.txt backup/ # Copy file
mv file.txt docs/   # Move or rename file
rm file.txt         # Delete a file

# System Information
whoami              # Show current username
uname -a            # Show system info
df -h               # Show disk usage
top                 # Show running processes

# Package Management (Ubuntu/Debian)
sudo apt update     # Update package list
sudo apt upgrade    # Upgrade all packages
sudo apt install git # Install a package
sudo apt remove git  # Uninstall a package

# Permissions
chmod 755 file.sh   # Change file permissions
sudo command        # Run command as administrator

💡 Pro Tip: Don’t be afraid of the terminal! The more you use it, the more powerful and efficient you become.

Concept 5: Linux Permissions and Users 🔐

A critical part of what is Linux is understanding its security and multi-user system. From the very beginning, Linux was designed to be used by many people at the same time on the same machine.

Types of Users in Linux:

1. Root User — The superuser or administrator. In Linux, what is Linux root user? It’s the user with unlimited access to the entire system. Equivalent to “Admin” in Windows.
2. Regular Users — Normal users with limited permissions, confined to their /home/username directory.
3. Groups — Users can be organized into groups to share permissions.

File Permissions in Linux:

These permissions apply to three categories: Owner, Group, and Others.

# Change permissions
chmod 755 script.sh    # rwxr-xr-x
chmod 644 index.html   # rw-r--r--

# Change file owner
chown username:group file.txt

This is why what is Linux known for — extreme security compared to other operating systems.