This course involves the use of artificial intelligence tools.

Your operating system is your first weapon. Learn to wield it.

Most servers on the internet run Linux. Most penetration testing tools run on Linux. And most people who try to break into cybersecurity get stuck at the same wall: they can't move confidently around a terminal.

This course removes that wall.

Instead of dumping a hundred commands on you, we start with how Linux thinks — the philosophy of small tools, chained together, with everything stored as a file. Once that clicks, the commands stop feeling like memorization and start feeling like logic.

You'll learn the architecture of a Linux system from hardware up through the kernel, shell and utility layers. You'll map the entire file system hierarchy and learn which directories actually matter during an assessment. You'll read your prompt like a pro to know instantly whether you're an unprivileged user or root.

Then we get practical. You'll run reconnaissance on a live box — who am I, where am I, what's running here. You'll create and manage files, decode every column of ls -la, and hunt down configuration files, backups and flags using find, locate and which. You'll finish with user and group management, and see exactly why /etc/shadow is the file every attacker wants.

Every section is demonstrated live in Kali Linux, so you're watching real output on a real terminal — not slides.

The course closes with three hands-on lab tasks covering user creation, hidden files and system enumeration, and file discovery. Do them. Terminal skill is muscle memory, and muscle memory only comes from typing.

No prior Linux experience required. Just a free virtual machine and a willingness to break things.

Course Curriculum

Course Introduction

Welcome & what this course covers
Why Linux is non-negotiable in cybersecurity
How to follow along (setting up your environment)

The Linux Philosophy

Principle 1: Everything is a file
Principle 2: Small, single-purpose programs
Principle 3: Chaining programs for complex tasks
Principle 4: Avoid captive user interfaces
Principle 5: Configuration stored in text files

Linux Architecture & Components

The bootloader (GRUB) and the boot process
The kernel: managing hardware and resources
Daemons: background services explained
The shell: Bash, Zsh and Fish
Graphics server, window managers (GNOME, KDE) and utilities
The four layers: hardware → kernel → shell → system utility

The Linux File System Hierarchy

Why Linux has no "C: drive" — the single root explained
Directory cheat sheet: /bin, /boot, /dev, /etc, /home, /lib
Directory cheat sheet: /media, /mnt, /opt, /root, /sbin, /tmp, /usr, /var
Demo: Exploring the root filesystem via terminal and GUI

Reading the Shell Prompt

Anatomy of the prompt: user, host and path
The tilde ~ and your home directory
$ vs #: knowing your privilege level at a glance
Demo: Switching to root with sudo su

Getting Help in the Terminal

Why nobody memorizes every command
Quick reference with --help
Deep documentation with man
Demo: Comparing wget --help and man wget

System Information & Reconnaissance

Who am I? — whoami and id
Where am I? — pwd and hostname
What is this box? — uname
Network recon — ifconfig, ip, netstat, ss
Process and session info — ps, who, env
Hardware enumeration — lsblk, lsusb, lsof, lspci
Demo: Running your first recon sequence on a live machine

Navigating the File System

The cd command and absolute vs relative paths
Moving backwards with cd ..
Navigation shortcuts worth knowing

Working with Files & Directories

Creating empty files with touch
Creating directories with mkdir
Moving and renaming with mv
Listing files with ls and the -la flag
Decoding ls -la: permissions, links, owner, group, size, timestamp, name
Demo: Create, list and rename files from scratch

Finding Files Like a Pentester

Checking if a tool is installed with which
Fast database searches with locate and sudo updatedb
The find command: the gold standard
find filters: -type, -name, -user, -size, -newermt
Suppressing permission errors with 2>/dev/null
Demo: Hunting backup files across the entire filesystem

User & Group Management

Privilege escalation: from unprivileged user to root
/etc/passwd — universally readable, no hashes
/etc/shadow — where the password hashes live
Running commands as another user: sudo and su
Account management: useradd, userdel, usermod
Group management: addgroup, delgroup
Changing passwords with passwd
Demo: Reading /etc/shadow with root privileges

Hands-On Lab Tasks

Lab overview and how to approach the tasks
Task 1: Create a user, add it to the root group, switch to it
Task 2: Create a hidden readme file, reveal it, and run system info commands
Task 3: Locate the files john.list and sudo using multiple methods
Lab walkthrough and solutions