This repository contains simple and easy-to-understand revision notes for the Linux course published on the YouTube channel Tech Mastery with Raj.
The course is designed for beginners as well as aspiring DevOps Engineers who want to build strong Linux fundamentals for real-world DevOps work.
The following topics are covered in this repository:
Linux Fundamentals Linux vs Windows Core Components of Linux Setting Up Linux on Windows and macOS Linux Directory Structure Linux User Management Linux File Management Commonly Used VI Editor Shortcuts Linux File Permissions Process Management Linux System Monitoring Basic Linux Networking Disk and Storage Management in Linux
Each topic is organised into separate folders at the root level of this repository for easy learning and revision.
You can also follow the complete video course on the YouTube channel Tech Mastery with Raj to learn Linux step by step for DevOps and IT careers.
- Free and Open Source: Linux does not require expensive licensing fees, making it a cost-effective choice for companies.
- Lower Maintenance Costs: Linux is stable and requires minimal maintenance, reducing operational expenses.
- Better Resource Utilization: Linux is lightweight and consumes fewer system resources compared to Windows.
- High Scalability: Linux efficiently scales from small embedded systems to enterprise data centers without performance degradation.
- Less Vulnerable to Malware: Linux has strong user privilege separation, making it more secure against viruses and malware.
- Frequent and Transparent Updates: Regular security patches ensure system stability without requiring frequent reboots.
- High Stability: Linux systems can run for years without crashes, ensuring better uptime and reliability.
rephrase it as per my channel Why Linux is Preferred Over Windows for DevOps Cost Effective Free and Open Source: Linux can be used without expensive license costs, which helps companies save money. Low Maintenance: Linux systems are stable and usually require less maintenance and troubleshooting. Better Performance Lightweight Operating System: Linux uses fewer system resources like CPU and memory compared to Windows. Highly Scalable: Linux works efficiently on small systems as well as large enterprise servers and cloud environments. Strong Security and Reliability More Secure: Linux has strong permission and user management features, making it less vulnerable to viruses and malware. Regular Security Updates: Security patches and updates are released frequently to keep systems secure and stable. High Stability and Uptime: Linux servers can run continuously for long periods without crashes or frequent restarts. Preferred by DevOps Engineers Most DevOps tools like Docker, Kubernetes, Jenkins, Ansible, and Terraform work more efficiently on Linux. Linux is widely used in cloud platforms, servers, automation, and production environments. Strong command-line support makes automation and scripting much easier for DevOps engineers.
🚀 That’s why Linux is considered one of the most important skills for every DevOps Engineer.
rephrase and change sequence and wordings as well Why DevOps Engineers Prefer Linux Instead of Windows Industry Standard for Servers and Cloud Most production servers, cloud platforms, and DevOps environments run on Linux. Popular DevOps technologies such as Docker, Kubernetes, Jenkins, and Ansible are mainly designed to work smoothly with Linux systems. Faster and More Efficient Linux is lightweight and uses fewer hardware resources like RAM and CPU. It delivers better performance even when handling heavy workloads and multiple processes. Better for Automation Linux provides powerful command-line tools and scripting support. Automation using Bash, Shell scripting, Python, and DevOps tools becomes easier and more effective on Linux. Secure and Stable Linux has strong security features such as user permissions and access control. It is less affected by malware and viruses compared to Windows. Linux systems are highly stable and can run for a long time without frequent reboots. Cost Saving for Organizations Linux is open source and does not require costly licenses. Companies can reduce infrastructure and maintenance costs by using Linux servers. Easy to Scale Linux can efficiently run on small virtual machines as well as large enterprise data centers. It is widely used in cloud computing, containers, and enterprise environments because of its scalability.
🚀 Learning Linux is one of the most important steps for becoming a successful DevOps Engineer.
plaintext +----------------------------------------------------+ | User Applications (Vim, Docker, Apache, etc.) | +----------------------------------------------------+ | Shell (Bash, Zsh, Fish, etc.) | <-- Part of the OS +----------------------------------------------------+ | System Libraries (glibc, libc, OpenSSL, etc.) | <-- Part of the OS +----------------------------------------------------+ | System Utilities (ls, grep, systemctl, etc.) | <-- Part of the OS +----------------------------------------------------+ | Linux Kernel (Process, Memory, FS, Network) | <-- Core of the OS +----------------------------------------------------+ | Hardware (CPU, RAM, Disk, Network, Peripherals) | +----------------------------------------------------+
(a) Hardware Layer
🔹 The physical components of the computer (CPU, RAM, disk, network interfaces, etc.). 🔹 The OS interacts with hardware using device drivers. (b) Kernel (Core of Linux OS)
🔹 The Linux Kernel is responsible for directly managing system resources, including:
Process Management – Schedules processes and handles multitasking.
Memory Management – Allocates and deallocates RAM efficiently.
Device Drivers – Acts as an interface between software and hardware.
File System Management – Manages how data is stored and retrieved.
Network Management – Handles communication between systems.
(c) Shell (Command Line Interface - CLI)
🔹 A command interpreter that allows users to interact with the kernel. 🔹 Examples: Bash, Zsh, Fish, Dash, Ksh. 🔹 Converts user commands into system calls for the kernel. (d) User Applications
🔹 End-user programs like web browsers, text editors, DevOps tools, etc. 🔹 Applications interact with the OS using system calls via the shell or GUI.
Rephrase and change wording and sequences as well, write like human Core Components of a Linux System +----------------------------------------------------+ | Applications (Docker, Vim, Nginx, Python, etc.) | +----------------------------------------------------+ | Shell (Bash, Zsh, Fish, Ksh, etc.) | +----------------------------------------------------+ | System Tools & Libraries | | (grep, ls, systemctl, glibc, OpenSSL, etc.) | +----------------------------------------------------+ | Linux Kernel | | (Process, Memory, File System, Networking) | +----------------------------------------------------+ | Physical Hardware | | (CPU, RAM, Disk, Network Devices, etc.) | +----------------------------------------------------+
- Hardware Layer
The hardware layer contains all the physical parts of the computer system.
Examples include:
CPU RAM Hard Disk / SSD Network Cards Keyboard, Mouse, and other devices
Linux communicates with these hardware components using device drivers.
- Linux Kernel
The kernel is the heart of the Linux operating system.
It directly interacts with the hardware and manages all major system operations.
Main responsibilities of the kernel:
Process Management Handles running processes, multitasking, and CPU scheduling. Memory Management Controls how RAM is allocated and used by applications. File System Management Manages files, directories, and storage devices. Device Management Uses device drivers to communicate with hardware. Network Management Controls network communication and data transfer between systems.
The kernel acts as a bridge between software and hardware.
- Shell
The shell is the command-line interface used to interact with Linux.
It accepts commands from users and sends them to the kernel for execution.
Common Linux shells:
Bash Zsh Fish Ksh Dash
For DevOps engineers, the shell is one of the most important components because automation and scripting are mainly performed through the command line.
- System Utilities and Libraries
Linux includes many built-in utilities and libraries that help the operating system and applications function properly.
Examples:
Utilities: ls, cp, grep, find, systemctl Libraries: glibc, OpenSSL, libc
These tools provide important functionality required by both users and applications.
- User Applications
These are the programs used by end users and administrators.
Examples include:
Docker Jenkins Web Browsers Text Editors Apache / Nginx Python Applications
Applications use system libraries and system calls to communicate with the Linux operating system.
🚀 Understanding these core Linux components is very important for system administrators, cloud engineers, and DevOps professionals.