terminal

Linux Fundamentals

From zero to Linux hero

The flagship course of Terminal 43. Takes a complete beginner from "what is Linux?" to confidently navigating the filesystem, managing processes, analyzing network traffic, and writing shell scripts -- all through hands-on challenges inside real Docker containers.

Beginner 72 challenges 15950 points ~55 hours

Course Content

0. Welcome to Linux

4 lessons

Introduction to the Linux operating system, the shell, and your very first commands.

What is Linux? 20min

The Shell -- Your New Home 20min

Getting Help -- man, --help, info 20min

Your Very First Commands 25min

1. Navigating the Filesystem

5 lessons

Learn the Linux directory tree, moving around with cd/ls/pwd, and creating, copying, moving, and deleting files.

The Linux Directory Tree 20min

Moving Around -- cd, ls, pwd 20min

Creating and Destroying -- mkdir, touch, rm, rmdir 20min

Copying and Moving -- cp, mv 20min

Finding Files -- find and locate 25min

2. Reading and Writing Files

7 lessons

Master file viewing, searching with grep, and text processing with sort, uniq, wc, cut, and tr.

Viewing Files -- cat, less, more, head, tail 20min

Searching -- grep 25min

Text Processing -- sort, uniq, wc, cut, tr 25min

Editing Files -- nano basics 20min

Comparing Files -- diff and comm 20min

File Challenge: Fix the SSH Config 20min

File Challenge: Parse the Access Log 15min

3. Permissions & Ownership

4 lessons

Understand rwx permissions, chmod, chown, chgrp, setuid, setgid, sticky bit, and sudo.

Understanding Permissions -- rwx, users, groups 25min

Changing Permissions -- chmod 20min

Ownership -- chown, chgrp 20min

Advanced Permissions 25min

4. Processes & Services

4 lessons

Learn to inspect, manage, and control processes and system services.

Understanding Processes -- ps, top, htop 25min

Job Control -- bg, fg, jobs, nohup, & 20min

System Services -- systemctl 25min

Monitoring Resources -- free, uptime, df 20min

5. Pipes, Redirection & Shell Scripting

4 lessons

Master I/O redirection, pipelines, and write your first shell scripts.

I/O Redirection -- >, >>, <, 2>, /dev/null 20min

Variables and Arithmetic 20min

Pipes -- | 20min

Shell Scripting Basics 35min

6. Networking Basics

5 lessons

Network configuration, connectivity tools, ports, packet capture with tcpdump and tshark.

Network Configuration -- ip, ifconfig, hostname 20min

Connectivity -- ping, traceroute, dig, nslookup 25min

Ports & Connections -- ss, netstat, curl, wget 25min

Downloading Files -- curl and wget 20min

Introduction to Packet Capture -- tcpdump, tshark 35min

7. Storage & Disk Management

4 lessons

Disk information, managing disk space, archives, and hard/symbolic links.

Disk Information -- df, du, lsblk, fdisk 20min

Archives and Compression -- tar, gzip, zip 20min

Working with Disk Space 25min

Links -- Hard links, Symbolic links 20min

8. Users & Groups Administration

4 lessons

Create and manage users, groups, and understand the underlying configuration files.

User Management -- useradd, usermod, userdel, passwd 25min

Understanding /etc/passwd, /etc/shadow, /etc/group 25min

User Environment -- .bashrc, .profile, aliases 20min

Sudo and Security -- sudoers, su 20min

9. Advanced Challenges & Capstone

1 lessons

Put everything together with hard challenges covering escape rooms, forensics, hardening, and the final gauntlet.

Putting It All Together 25min