Linux Beginner Labs: Foundations (Understand Linux, Not Just Commands)

This lab helps you understand how Linux works internally, not just type commands.
By the end of these labs, Linux will feel logical, not intimidating.

Before You Start The Lab (Very Important).

What You Need

You can use any Linux environment:

• Ubuntu Desktop / Server

• Linux VM

• Cloud VM

• WSL (Windows Subsystem for Linux)

No special distro required. Linux concepts are universal.

Core Rule Before We Begin

In Linux, everything is a file, everything is text, and everything is discoverable.

Keep this in mind throughout the labs.

LAB 1: Understanding Where You Are (Navigation Basics)

Step 1: Check Your Current Location

pwd

Definition:

pwd = Print Working Directory

It tells you:

• Where you are in the filesystem

• Which directory commands will act on

📌 Linux always knows where you are, just like a GPS.

Step 2: List Files and Directories

ls

Definition

ls = List directory contents

Linux does not show files automatically like Windows Explorer. You must ask explicitly.

Step 3: View Hidden Files

ls -a

Explanation

Files starting with “.” are hidden configuration files.
Linux hides configs by default to reduce clutter.

Examples:

• .bashrc

• .profile

• .ssh

Key Understanding

Your home directory is your personal workspace, not the whole system.

LAB 2: Linux Filesystem Hierarchy (CRITICAL LAB)

Step 1: List the Root Directory

ls /

You’ll see directories like:

bin etc home var usr tmp dev proc

What These Mean (Memorize the Purpose, Not the Names)

Step 2: Explore Configuration Files

ls /etc

📌 You’ll notice:

• Plain text files

• No binaries

• Human-readable configs

👉 Linux is configured by editing text, not clicking GUIs.

Step 3: View Logs

ls /var/log

Logs answer:

• What happened?

• When?

• Why something failed?

This is where real troubleshooting starts.

Key Understanding

If you know /etc and /var/log, you can debug most Linux systems.

LAB 3: Understanding the Terminal & Shell

Step 1: Identify Your Shell

echo $SHELL

Definition

A shell is a program that:

• Reads commands

• Interprets them

• Sends them to the kernel

Common shells:

• bash

• zsh

• sh

Step 2: Understand the Prompt

Example:

user@server:/home/user$

📌 Never ignore the prompt; it tells you your power level.

Key Understanding

Linux is multi-user by design. Knowing who you are matters.

LAB 4: How Linux Finds Commands

Step 1: Locate a Command

which ls

Explanation

Linux searches directories listed in $PATH.

Step 2: View PATH

echo $PATH

You’ll see directories like:

/usr/bin:/bin:/usr/sbin

Linux:

1. Reads command

2. Searches PATH left → right

3. Executes first match

Key Understanding

If it’s not in $PATH, Linux can’t run it by name.

LAB 5: Linux Help Systems (THIS MAKES YOU INDEPENDENT)

Step 1: Use the Manual

man ls

What You Would be Seeing

• NAME → What the command does

• SYNOPSIS → How to use it

• DESCRIPTION → Detailed behavior

• OPTIONS → Flags & switches

📌 Man pages are official documentation.

Step 2: Quick Help

ls --help

This gives:

• Short descriptions

• Common options

• Faster lookup

Step 3: Info Pages

info coreutils

Structured, long-form documentation.

Key Understanding

Linux experts don’t memorize commands; they know how to read documentation fast.

LAB 6: Files Are Text (Viewing Safely)

Step 1: View a File Safely

cat /etc/os-release

This shows:

• OS name

• Version

• Distro details

Step 2: Use a Pager (Recommended)

less /etc/passwd

Why less?

• Scroll up/down

• Doesn’t flood terminal

• Safe for large files

Key Understanding

Config files explain your system better than tutorials.

LAB 7: Navigation Mastery

cd /
cd /etc
cd /var/log
cd ~
cd ..

Definitions

• cd → change directory

• ~ → home directory

• .. → parent directory

📌 You should be able to move without thinking.

LAB 8: Understanding File Types (Linux Is Not Windows)

This lab teaches you how Linux identifies file types without relying on extensions.

Step 1: Identify File Types

ls -l

What You’re Seeing

The first character in each line tells you the file type:

Why This Matters

Linux does not rely on .exe, .txt, .jpg extensions. It reads metadata instead.

Step 2: Use the file Command

file /bin/ls

The file command inspects the file’s magic number – a signature inside the file – to determine its type.

Examples you might see:

• ELF 64-bit executable
• ASCII text
• Shell script
• JPEG image data

Key Understanding

Linux determines file type by content, not name. This is why renaming a file doesn’t change what it is.

LAB 9: Understanding Absolute vs Relative Paths

Navigation becomes effortless once you understand how Linux resolves paths.

Step 1: Absolute Path

cd /etc

Meaning

Starts from / (root). Always the same, no matter where you are.

Step 2: Relative Path

cd ../var/log

Meaning

Starts from your current directory. .. = parent . = current directory

Step 3: Combine Both

cd /etc/../var/log

Linux resolves this to:

/var/log

Key Understanding

Linux resolves paths before executing commands. This is why scripts can use relative paths safely.

LAB 10: Creating, Copying, Moving, and Deleting Files

(The Safe Way)

Beginners often fear breaking things. This lab teaches safe file manipulation.

Step 1: Create Files

touch notes.txt

Explanation

touch updates timestamps, but if the file doesn’t exist, it creates it.

Step 2: Create Directories

mkdir projects
mkdir -p projects/app1/logs

-p creates parent directories automatically.

Step 3: Copy Files

cp notes.txt notes-backup.txt

What the command does

This command copies the file notes.txt and creates a new file called notes-backup.txt.

Nothing is deleted or moved, it’s a straight duplication.

Recursive Copy

cp -r projects projects-backup

What the command does

This command copies an entire directory named “projects” including all files and subfolders inside it, and creates a new directory called projects-backup.

Nothing is moved or deleted. It’s a full recursive copy.

Step 4: Move/Rename Files

mv notes.txt archive.txt

What the command does

This command renames the file notes.txt to archive.txt.

Nothing is copied. Nothing is duplicated. The original file name simply changes.

Linux uses the same command for moving and renaming.

Step 5: Delete Files Safely

rm archive.txt

Delete Directories

rm -r projects-backup

Safer Delete (Prompt Before Removing)

rm -i archive.txt

Key Understanding

Linux does not have a recycle bin. Deletion is permanent unless you use safety flags.

LAB 11: Wildcards & Pattern Matching (Powerful Skill)

Wildcards let you operate on multiple files at once.

Step 1: Match All Files

ls *

Step 2: Match Files Starting With “a”

ls a*

Step 3: Match Files Ending With “.log”

ls *.log

Step 4: Match Single Characters

ls file?.txt

Matches:

• file1.txt
• fileA.txt

Not matched:

• file10.txt

Step 5: Match Ranges

ls file[1-5].txt

Key Understanding

Wildcards are handled by the shell, not the command. The shell expands patterns before running the command.

LAB 12: Redirection & Pipes (The Heart of Linux Power)

Linux commands are small tools. Pipes let you chain them into powerful workflows.

Step 1: Redirect Output to a File

ls /etc > etc-list.txt

> overwrites the file.

Step 2: Append Output

ls /var >> etc-list.txt

>> appends instead of overwriting.

Step 3: Redirect Errors

ls /root 2> errors.txt

2> captures error messages.

Step 4: Pipe Output to Another Command

ls /etc | grep ssh

Explanation

| sends output of one command into another.

Step 5: Count Lines

ls /etc | wc -l

Key Understanding

Pipes turn Linux into a modular system where small tools combine into powerful workflows.

LAB 13: Searching Files & Directories (Find Anything)

Searching is a core Linux skill.

Step 1: Search for Files by Name

find /etc -name "*.conf"

Step 2: Search by Type

find /var -type d

-type d = directories -type f = files

Step 3: Search Inside Files

grep "root" /etc/passwd

What the command does

This command searches for the word “root” inside the /etc/passwd file and prints any lines that contain it.

/etc/passwd is the file that stores all user accounts on the system.

Step 4: Recursive Search

grep -R "sshd" /etc

Step 5: Case-Insensitive Search

grep -i "ubuntu" /etc/os-release

What the command does

This command searches every file and subdirectory inside /etc for any lines that contain the text “sshd”.

It performs a recursive search, meaning it goes through:

• /etc
• All folders inside /etc
• All files inside those folders

…and prints any matches.

Key Understanding

find locates files. grep searches inside files. Together, they are your Linux search engine.

LAB 14: Understanding Processes

(Linux Is Always Running Something)

Processes are programs in motion.

Step 1: View Running Processes

ps aux

What You See

• USER
• PID (process ID)
• CPU usage
• Memory usage
• Command

Step 2: Real-Time Process Viewer

top

Or the improved version:

htop

Step 3: Kill a Process

kill <PID>

Force kill:

kill -9 <PID>

Step 4: Find a Process by Name

pgrep ssh

Step 5: See Process Tree

pstree

Key Understanding

Linux is a living system. Processes are the heartbeat.

LAB 15: Environment Variables (The Hidden Settings of Linux)

Environment variables control how Linux behaves.

Step 1: View All Variables

printenv

Step 2: View a Specific Variable

echo $HOME
echo $USER
echo $PATH

Step 3: Create a Temporary Variable

export GREETING="Hello Linux"
echo $GREETING

Step 4: Make It Permanent

Add to ~/.bashrc:

export GREETING="Hello Linux"

Reload:

source ~/.bashrc