Introduction
Welcome to Kali Linux. In this first lab, you will discover where Kali came from, why people use it for security work, and how it fits into the Linux family. Then you will use a real security tool to discover a service in your prepared training environment.
You do not need Linux, networking, or Docker experience. Your environment and training target are ready for you; there is nothing to download or install. Use the Terminal interface for the short hands-on experience. This lab does not require the Desktop.
By the end, you will be able to explain Kali's purpose, recognize what it shares with other Linux distributions, and connect your first discovery to the skills you will learn next.
Meet Kali and Its Origins
In this step, you will discover why Kali exists and how it grew from an earlier security-testing project.
A Toolkit Built Around Questions
Imagine that a team has asked you to check its training server. Before deciding whether anything needs fixing, you need evidence: Which services can be reached? What does a website return? What information travels across the network?
Kali Linux is an open-source Linux distribution based on Debian and designed for penetration testing and security auditing. A penetration test is an authorized investigation of a system's security. An audit examines security controls and evidence. Both require people who can choose tools and interpret what they observe.
A Linux distribution combines the Linux kernel—the core that manages resources—with system utilities, software packages, and configuration. Different distributions organize these pieces around different needs. Kali organizes them around security work.
From BackTrack to Kali
Kali grew out of BackTrack, an earlier Linux distribution focused on security testing. Experience maintaining BackTrack helped shape a new Debian-based platform. Kali's first release arrived on March 13, 2013.
| Stage | What changed |
|---|---|
| BackTrack | Brought security-testing tools into a dedicated working environment. |
| Kali's first release in 2013 | Carried that experience into a rebuilt Debian-based distribution. |
| Kali today | Continues as a maintained platform for security work, available in several forms, including virtual machines and containers. |
You do not need to memorize dates or version names. The useful connection is that Kali developed around a practical need: giving security practitioners a maintained environment for their work. You can explore the official Kali history later.
Questions Before Tools
Different tools answer different questions:
| Your question | Example tool |
|---|---|
| What network services can I reach? | Nmap |
| What traffic is being exchanged? | Wireshark or tcpdump |
| How resistant are these password hashes to guessing? | John the Ripper |
You will meet these tools later in the course. Today, you will try just one small service-discovery task. There is no history quiz or command to run in this step. Select Continue when you are ready to compare Kali with other Linux distributions.
Understand Kali's Place in the Linux Family
In this step, you will compare Kali with general-purpose Linux distributions and understand what you need to begin this course.
A Familiar Foundation, a Different Focus
Kali is part of the Linux family. Ubuntu and Debian are also Linux distributions. Kali's distinctive feature is its focus on security work; the underlying ideas of files, users, processes, and networking still apply.
| Aspect | General-purpose distributions, such as Ubuntu | Kali Linux |
|---|---|---|
| Main focus | A broad range of desktop, development, and server tasks | Security testing and auditing |
| Software selection | Organized around general computing needs | Organized around security workflows |
| Everyday foundations | Files, users, processes, networking, and terminals | The same foundations remain essential |
| Security tools | Can be installed as needed | A dedicated package ecosystem and tool selection support security work |
A tool such as Nmap can run on other operating systems too. Kali brings tools and supporting packages together in a security-focused environment. Different Kali images include different selections; you should not expect every tool to be installed in every Kali environment. Read more in the official Kali introduction.
Tools Need an Operator
Having Kali available gives you a place to work. You will also learn how to ask a clear question, select a tool, interpret its results, and decide what to investigate next.
For example, discovering an accessible service tells you that the service accepts connections. More evidence is needed to determine whether it has a security problem. This distinction will matter in your first experience.
You can begin this course without previous Linux experience: the early labs teach the foundations before later labs ask you to use them independently. There is no need to replace your own operating system to follow along.
Your Prepared Practice Environment
LabEx provides a Kali environment and specific training targets. Use only the target and port given in each exercise. In professional work, confirming permission and the agreed testing scope is also part of preparing a security assessment.
For today's exercise, the entire target is one local service inside your Kali environment. You will enter Kali through the supplied entry command, then perform one bounded check. The platform handles the environment preparation.
No command or memorization test is required in this step. Select Continue to try your first tool.
Discover Your First Training Service
In this step, you will enter Kali and use Nmap to discover a prepared local training service.
Enter the Prepared Environment
Open the Terminal interface and click inside it. A terminal lets you send instructions by typing commands and pressing Enter. Copy only the command itself, not any prompt shown before it.
The supplied kali command opens the prepared Kali environment. Type it and press Enter:
kali
You should now see a Kali prompt. Stay in this terminal for the rest of the experience. If you open a new Terminal later, run kali there before repeating the check.
Ask One Small Question
A service is a running program that accepts requests. A port is a numbered connection endpoint; a single machine can provide multiple services on different ports.
We have prepared a training service on port 8080. Its address is 127.0.0.1, which refers to the environment you are currently inside. Here, that means Kali itself. This address and port are the complete scope of this exercise.
Nmap is a tool for discovering hosts and services. The following command is prepared for this first experience: -sT asks for an ordinary TCP connection check, and -p 8080 limits it to one port. The final address names the target. You do not need to memorize these options; a later lab will teach you to choose scans and interpret their results independently.
Run the command exactly as shown:
nmap -sT -p 8080 127.0.0.1
After a short wait, look for a line with this shape:
PORT STATE SERVICE
8080/tcp open ...
The final column may show a service label. Focus on open for now: Nmap was able to connect to the training port. The timing, version banner, and other lines can vary.
You have just turned a question—“Is a service reachable here?”—into an observation. An open service is a starting point for investigation; this result alone does not establish a vulnerability.
LabEx automatically records this demonstration's scan result for the step check. You do not need to create or save a report yourself. Select Continue after the command finishes. If the check fails, confirm you entered Kali, then repeat the exact scan above.
Connect This Experience to Your Learning Path
In this step, you will connect your first service discovery to the practical skills you will build throughout the course.
From Following a Command to Working Independently
Today you used a prepared command and target. As you progress, you will learn to make those choices yourself and explain the evidence you collect.
| A question you might now have | Where the course takes you |
|---|---|
| Where should I keep my practice files and notes? | Navigating and managing files in Kali |
| How do I find useful information in a long result? | Reading and filtering tool output |
| How do I find tools or deal with a stalled program? | Security tools, processes, and logs |
| How do addresses, ports, and target names fit together? | Networking foundations |
| How do I choose a scan and identify a service? | Nmap and DNS reconnaissance |
| What can I observe after finding a web service? | HTTP inspection and network traffic |
Later, you will also explore password tools, Metasploit, and access control. Each topic builds on your ability to operate the environment and explain what the tools actually show.
How to Use the Course
A Guided Lab, like this one, explains the task and provides the steps. A Challenge asks you to apply previously taught skills with fewer instructions. Use both to move from recognition to independent practice.
Each exercise prepares its own environment. You do not need to carry files or a running service from this lab into another one. When a later exercise asks you to enter Kali, its instructions will show you how.
The hands-on check in the previous step confirmed your service discovery. This final reading step has no additional command or quiz. Select Continue to finish. Your next practical foundation is learning to navigate and organize files in Kali.
Summary
You explored Kali's origins in BackTrack, its Debian foundation, and its focus on security work. You compared it with general-purpose Linux distributions and saw why Linux foundations and careful interpretation matter.
You also entered a prepared Kali environment and used Nmap to discover a reachable local training service. That was your first observation, not a claim that the service was vulnerable. Next, build the file-management and output-reading skills that will help you use security tools independently.
