Linux/Unix Tutorial

Linux is one of the most widely used open-source operating systems. It's fast, secure, stable, and powers everything from smartphones and servers to cloud platforms and IoT devices. Linux is especially popular among developers, system administrators, and DevOps professionals.

Linux is:

• A Unix-like OS used in servers, cloud infrastructure, supercomputers, personal computers and embedded systems.
• Reliable and secure, making it ideal for web hosting, networking, and automation.
• Preferred in DevOps, where it's used for scripting, configuration, containerization (Docker), and CI/CD pipelines.
• Open-source and customizable, giving users full control over their systems and workflows.

This Linux tutorial is designed for both beginners and experienced professionals. It covers everything from basic commands and file management to advanced topics like file permissions and shell scripting.

1. Understanding Linux Basics

In this section, we will cover the basics of Linux operating system, how it works, and how it's different from Unix. We'll learn about the concept of Linux distributions (distros), why they exist, and how to choose the right one based on your needs—whether you're a beginner, developer, or system admin.

• Introduction to Linux Operating System
• What are Linux Distribution?
• Choosing a Linux Distribution
• Difference between Linux/Unix

Installing Linux

Before getting started with Linux, we need to set it up on your system. Here are two common ways to do this:

• Installing Linux Using a Virtual Machine
• Creating a Dual Boot System with Linux and Windows

2. Linux Commands

Linux commands are instructions entered in the terminal to perform tasks such as navigating directories, managing files, monitoring system performance, and installing software. Here are the most commonly used Linux commands along with a complete list:

• 25 Basic Linux Commands For Beginners 
• Complete Linux Commands

3. Linux File System

The Linux file system organizes data in a hierarchical structure, starting from the root ("/"). It defines how files and directories are stored, accessed, and managed, ensuring efficient system navigation and resource organization. In this section, we’ll explore its key components including the directory structure, file types, absolute and relative paths, and mount points.

• Linux File System
• Linux File Hierarchy Structure
• Linux Directory Structure
• File System Navigation Commands in Linux
• Absolute and Relative Pathnames in UNIX

4. File Management in Linux

File management in Linux is all about creating, viewing, editing, moving, copying, and deleting files and directories using both the command line and graphical tools. In this section, we’ll cover essential file management commands like ls, cd, cp, mv, rm, and touch, along with concepts like file paths, wildcards, and hidden files.

• File Management in Linux
• Files Listing: ls command
• Creating Files: touch command
• Displaying File Contents: cat command
• Copying a File: cp command
• Moving and Renaming a File: mv command
• Deleting a File: rm command

File Permissions in Linux

• Permissions in Linux
• Files Listing by ls command
• Changing Security Permissions by chmod command
• Soft and Hard links in Unix/Linux
• Advance File Permissions in Linux
• Find a File in Linux by Find Command
• View the Content of File in Linux by cat Command

5. Package Management

Package management in Linux involves installing, updating, and removing software using package managers like apt, yum, or dnf. It simplifies handling software dependencies and ensures systems stay updated and secure.

• Understanding Package Managers and systemctl
• apt-get command in Linux with Examples 
• Debian Software Package Management(dpkg) in Linux
• How to Install RPM Packages on Linux?
• Installing YUM 
• YUM Commands for Linux Package Management
• Zypper (openSUSE)
• Pacman command in Arch Linux

Linux Packages Manager

• dpkg Package Manager
• yum Package Manager
• dnf Package Manager
• apt-get Package Manager

6. User and Group Management

Managing users and groups in Linux involves creating, modifying, and controlling user accounts, assigning permissions, and organizing users into groups for efficient access control and system security.

• How to Check the Groups a User Belongs to in Linux
• sudo command in Linux with Examples
• User Management in Linux
• awk command
• id username
• sudo useradd username
• passwd udername
• changing user ID
• modifying group ID
• Permissions in Linux
• chmod - Change permission
• passwd command in Linux with Examples

7. Linux Networking

Linux networking covers everything from configuring IP addresses and managing network interfaces to setting up firewalls, monitoring traffic, and enabling communication between devices and servers:

• Network configuration and trouble shooting commands in Linux
• How to configure network interfaces in CentOS?

Linux Firewall

• What is Linux Firewall?
• How to setup firewall in Linux?
• Basic iptables commands
• Managing firewall configuration

8. Shell Scripting

Shell scripting is writing a series of commands in a script file to automate tasks in a Linux or Unix shell. It simplifies repetitive tasks like file management, system monitoring, and process automation, using languages like Bash or other shell environments:

• Introduction to Linux Shell and Shell Scripting
• What is Kernel?
• What is Shell?
• Different Linux Shells
• Difference between Shell and Kernel
• What is a Terminal?

Creating and Running Shell Scripts

• Creating a Shell Script
• Defining the Shell Script Interpreter (#!/bin/bash)
• Comments in the Shell Script
• Storing and Displaying Messages in a Shell Script
• Storing the Output of Commands
• Exit Codes of Shell Commands

Variables in Shell Scripting

• Shell Scripting – Shell Variables
• Shell Scripting – Different Types of Variables
• Rules for Variable Definition
• Variable Types

Bash Scripting

• Bash Scripting – Introduction to Bash and Bash Scripting
• Bash Script – Define Bash Variables and Its Types
• Working of Bash Scripting
• How To Run Bash Script In Linux?
• Bash Scripting - Functions
• Difference between Shell (sh) and Bash
• Basic Operators in Shell Scripting

Advanced Topics in Shell Scripting

• Making Your Own Linux Shell in C
• 30+ Common Linux Shell Script Examples

9. System Administration

System administration in Linux involves managing and maintaining Linux systems, including tasks like user management, file permissions, software installation, network configuration, and monitoring system performance. It ensures the system operates efficiently and securely.

• What is Linux System Administration?
• Beginner's Guide to Linux System Administration
• Basic Linux Commands and File System Navigation
• User Management in Linux
• Group Management in Linux

Monitoring and Troubleshooting

• How to Monitor System Usage, Outages, and Troubleshoot Linux Servers

Linux Systemd and Boot Process

• Introduction to Systemd and its Components
• Boot Process in Linux
• How to Control Systemd Services on a Remote Linux Server

10. Advance Linux Concepts

• Overview of the Linux Kernel
• Understanding Linux Loadable Kernel Modules (LKMs)
• Virtualization with Docker Containers

Networking Services

• Dynamic Host Configuration Protocol (DHCP)
• Domain Name System (DNS)
• File Transfer Protocol (FTP)

Web Server Administration

• Difference between Apache and Nginx
• How to Install and Configure Nginx from Source on Linux

11. Linux Cloud

• The Role of Linux in Cloud Computing and DevOps
• Linux commands in Devops
• Deploying and Managing Linux in the Cloud

Linux Interview Questions

Here are the top 70 most commonly asked Linux interview questions, covering essential topics like commands, shell scripting, system administration, networking, and troubleshooting:

• Top 70 Linux Interview Questions

Best Approach to Learn Linux

Here’s the step-by-step approach to learn and master Linux efficiently and effectively:

1. Understand Linux Basics: Start by learning what Linux is, its distributions (distros), and its core components like the kernel, shell, and file system.
2. Install a Linux Distro: Choose a beginner-friendly distribution like Ubuntu or Fedora and set it up on your system (dual boot or virtual machine).
3. Learn Basic Commands: Familiarize yourself with essential commands like ls, cd, pwd, cp, mv, rm, and mkdir. Practice navigating directories and managing files.
4. Explore the File System: Understand the Linux file structure, including /home, /var, /etc, and /usr. Learn how permissions work using chmod, chown, and ls -l.
5. Work with Text Editors: Get comfortable with terminal-based editors like Vim or Nano for creating and editing files.
6. Understand Package Management: Learn how to install, update, and remove software using package managers like apt (Debian-based) or yum/dnf (Red Hat-based).
7. Explore Shell Scripting: Start writing basic shell scripts to automate repetitive tasks and understand how shell scripting integrates with Linux commands.
8. Manage Processes and Services: Use commands like ps, top, and kill to manage processes and explore system services using systemctl.
9. Networking in Linux: Understand networking basics like IP configuration (ifconfig or ip), checking connectivity (ping), and managing firewall settings (ufw or iptables).
10. Learn Advanced Tools: Explore tools like grep, awk, sed, and cron for text processing and task scheduling.
11. Work on Real Projects: Set up a web server using Apache or Nginx, configure SSH for remote access, or create a simple home automation script.
12. Stay Updated: Regularly practice and stay updated with the latest Linux features, commands, and best practices by joining Linux forums and following tutorials.

By following this structured approach, you’ll gain both the foundational knowledge and practical experience needed to use and manage Linux systems effectively.

Linux Certifications

Earning a Linux certification validates your expertise in Linux administration, troubleshooting, and system management, opening doors to career opportunities in IT and networking.

Why Pursue a Linux Certification?

• Validates technical skills and increases job prospects.
• Enhances credibility for roles in system administration, DevOps, and cloud computing.
• Provides in-depth knowledge for efficient Linux management.

Career & Jobs in Linux 2025

Linux offers diverse career opportunities across industries. Here’s a list of the best career options available for professionals with Linux expertise, along with their average salaries.

Also read - 5 Tips to Make a Career as a Linux Kernel Developer

List of Companies Use Linux

These are some popular companies that use Linux in their workflow: