Day 1: Python and the Linux Terminal

CyberQuest Summer Camp - day deck

This is your hands-on companion to the main course deck. The main deck (Interactive_Slides.html) sends you to specific Parts here and to Modules in the notebook, then back. You can also run this deck on its own, top to bottom, with the Next arrow.

Morning Kickoff: Motivation & News (09:00 AM - 09:15 AM)

• Case Profile: The 2014 Sony Pictures Hack. Attackers compromised network architectures using targeted data deletion tools, revealing confidential emails and unreleased files. This demonstrates how cyberattacks can have real-world political consequences.

Teaching Session I: Core Lecture (09:15 AM - 11:15 AM)

Introduction to Computer Programming using Python

Python is an interpreted, high-level, general-purpose programming language. Because its syntax focuses heavily on readability, it is a widely used tool among security professionals for writing automated scanners and security tools. * Variables: Named containers that store values. * Syntax: The grammar rules regulating code configuration. * Data Types: Strings (textual data like "admin"), Integers (whole numbers like 80), and Booleans (logical evaluations representing True or False).

Computer Networking Foundations

• Internet Protocol Address (IP Address): A unique numerical identifier assigned to a device or network interface.
• Data Packet: A formatted unit of data carried by a packet-switched network. Contains control metadata (headers) and user data payloads.
• Routing: The functional process of selecting paths across network nodes to guide packets from their source to their destination.
• HTTP vs HTTPS: Hypertext Transfer Protocol (HTTP) transmits network requests in unencrypted plain text. Hypertext Transfer Protocol Secure (HTTPS) uses Transport Layer Security (TLS) cryptographic protocols to encrypt communication channels, preventing eavesdropping.

The Linux Operating System Command Line Interface (CLI)

Cybersecurity systems, cloud networks, and penetration testing platforms like Kali Linux rely on a text-based command line interface instead of a graphical user interface. * pwd (Print Working Directory): Outputs the full path of the current working folder. * ls (List Directory Contents): Displays files inside the current working folder. * cd (Change Directory): Moves the user into a different directory folder. * mkdir (Make Directory): Generates a brand-new directory folder. * echo (Display text line): Prints arguments to the standard output screen. * cat (Concatenate): Reads file inner text and displays it directly to the terminal.

Teaching Session II: Labs & Interactive Tools (11:45 AM - 01:45 PM)

Practical Interactive Tools for Today

1. CodeCombat: Navigate programming levels by typing functional Python loops and variable calls.
2. OverTheWire Bandit: Connect via Secure Shell (SSH) and run commands (ls, cd, cat) to search for text-based authentication keys hidden in files.

Recap & Tomorrow's Horizon (04:15 PM - 04:30 PM)

• Summary: Today we mastered core variables, network routing differences, and basic terminal control commands.
• Tomorrow Preview: We will move from basic technical systems to security management frameworks, examining threats, vulnerability analysis, and the legal limits of hacking.

Your plan for today

6 parts. Press Next to move in order.

1. Part 1. Get oriented - 4 slides
2. Part 2. Learn the basics - 25 slides
3. Part 3. Code along - 1 slide
4. Part 4. Play the free tools - 3 slides
5. Part 5. Test yourself - 4 slides
6. Part 6. Wrap up - 1 slide

PART 1 OF 6

Get oriented

Objectives, key terms, a picture, and the news.

This part is 4 slides. Press Next to begin.

Learning objectives

By the end of today you can: - Explain what Python is and why it is used in cybersecurity. - Use variables, data types, and a loop. - Navigate a Linux terminal and read your first hidden password in OverTheWire Bandit.

Vocabulary (acronyms expanded and defined)

• Python: a popular, easy-to-read programming language (named after the comedy group Monty Python, not the snake).
• CLI = Command Line Interface: a text-only way to control a computer by typing commands.
• OS = Operating System: the software that runs a computer, such as Windows, macOS, or Linux.
• Linux: a free, open-source operating system that runs most web servers, phones (Android), and supercomputers.
• SSH = Secure Shell: a tool to safely log in to another computer over the network.
• IDE = Integrated Development Environment: an app for writing and running code.
• Syntax: the grammar rules of a programming language.
• Variable: a named box that stores a value.

Picture it

   YOU type a command  ->  [ TERMINAL ]  ->  the computer obeys
        ls                                     shows your files
        cd Desktop                             moves into a folder
        cat secret.txt                         prints a file

A loop is like telling a robot: "take a step, repeat 5 times."

In the news (real and verifiable)

Python is consistently ranked among the most popular programming languages in the world in the annual Stack Overflow Developer Survey and the TIOBE index. Security teams love it because you can automate boring tasks in a few lines. Most websites you visit run on Linux servers, which is why learning the terminal is a real career skill.

PART 2 OF 6

Learn the basics

Now go deeper: the core ideas step by step, with quick knowledge checks.

This part is 25 slides. Press Next to begin.

What is Python?

The language of automation

• A popular, easy-to-read programming language.
• Named after the comedy group Monty Python, not the snake.
• Security teams use it to automate tasks in just a few lines.

print("Hello, CyberQuest!")

Syntax: the grammar of code

Rules the computer follows

Syntax means the rules a language expects. Python cares about spelling, punctuation, and indentation (spaces at the start of a line).

for step in range(3):
    print(step)   # indented = inside the loop

Variables: labeled boxes

Storing information

A variable stores a value so you can reuse it. = means store the value on the right into the name on the left.

agent_name = "Ada"
missions = 3
print(agent_name, missions)

Knowledge check

A variable is best described as...

Data types

The kinds of values

• str (string): text in quotes, like a password.
• int (integer): whole numbers like 42.
• float: decimals like 3.14.
• bool (boolean): True or False.

Knowledge check

What data type is the value 42 ?

Loops repeat work

Do it again, automatically

A loop runs the same block many times. Moving a hero through a maze in CodeCombat is just a loop of steps.

for i in range(5):
    print("Mission", i, "ready")

Knowledge check

How many times does for i in range(3): repeat?

How Python runs your code

Illustration

Readable code goes in, the interpreter runs it immediately, and you see the result. No slow compile step.

Your first commands

print and comments

The print function shows text. A # starts a comment, a note for humans that Python ignores.

# this is a comment
print("Hello, CyberQuest!")

Getting input

Talking to the user

input pauses and waits for the user to type. What it returns is always text (a str).

name = input("Your name: ")
print("Welcome", name)

The four data types

Reference table

Doing math

Arithmetic operators

Knowledge check

What is 2 ** 8 ?

Comparisons and booleans

Asking yes or no questions

Comparisons give a bool. == means equal, != not equal, > greater than, < less than.

print(5 > 3)     # True
print(5 == 6)    # False

Making decisions

The if statement

An if runs code only when a condition is True. else covers the other case.

pw = "sunshine"
if len(pw) < 12:
    print("Too short")
else:
    print("Good length")

How an if statement decides

Illustration

The condition is checked once. Exactly one branch runs.

Lists

Storing many values

A list holds many values in order, written in square brackets.

ports = [22, 80, 443]
print(ports[0])     # 22 (first item)
print(len(ports))   # 3

Indexing and slicing

Reaching into text and lists

Counting starts at 0. You can grab one item or a range.

word = "flag"
print(word[0])    # f
print(word[1:3])  # la

A loop, step by step

Illustration

Check, run the block, update the counter, repeat until the condition is false.

While loops

Repeat until a condition changes

A while loop repeats as long as its condition stays True. Be sure something changes, or it never stops.

tries = 0
while tries < 3:
    print("attempt", tries)
    tries = tries + 1

Knowledge check

How many times does for i in range(5) run?

SSH: logging in safely

Illustration

SSH encrypts the whole session, so passwords and commands cannot be read on the network.

Linux commands you will use

Quick reference

When code breaks

Reading errors

Errors are normal. Python prints the line and the problem. A SyntaxError means a typo in the grammar; a NameError means you used a name that does not exist yet. Read the last line first.

Python functions

Python primer — reusable code blocks

Reusable blocks of code

A function is a named block that runs when you call it. Use def to define it, then call it by name. Functions stop repetition and make code readable.

def greet(name):
    message = "Hello, " + name
    return message

print(greet("Ada"))   # Hello, Ada

Python file I/O

Python primer — reading and writing files

Reading and writing files

open() returns a file object. Use with so the file closes automatically even if an error happens.

# write a file
with open("log.txt", "w") as f:
    f.write("scan started\n")

# read it back
with open("log.txt", "r") as f:
    print(f.read())   # scan started

Knowledge check

What keyword starts a function definition in Python?

The OSI model

A 7-layer map of how data travels

Data travels DOWN the layers when sending, UP when receiving. Each layer adds a header (encapsulation).

What happens when you type a URL?

DNS to TLS in 5 steps

Step 3 (TLS) only happens for HTTPS. Without it, anyone on the same Wi-Fi can read the data.

The Linux filesystem tree

Everything is a file

  /              (root, the top of everything)
  ├── etc/       (configuration files: passwd, hosts)
  ├── home/      (each user's personal folder)
  │   └── ada/
  ├── var/       (logs, changing data)
  │   └── log/
  ├── tmp/       (temporary files, wiped on reboot)
  ├── bin/       (basic programs: ls, cat, cp)
  └── usr/       (installed software)

Pipes and redirection

Connecting commands together

The pipe | sends one command's output into another. Redirection > sends output to a file.

# find lines containing "root" in the password database
cat /etc/passwd | grep root

# save those matches to a file
cat /etc/passwd | grep root > found.txt

# count how many matches
cat /etc/passwd | grep -c "bash"

Numeric: IPv4 address space

How many addresses exist?

An IPv4 address is 4 bytes (32 bits). Total unique addresses:

2^32 = 4,294,967,296   (about 4.3 billion)

A /24 subnet (like your home Wi-Fi 192.168.1.x) gives:

2^8 = 256 total addresses
256 - 2 = 254 usable  (subtract network + broadcast)

This is why IPv6 was invented: 4.3 billion addresses ran out with billions of phones and IoT devices online.

Knowledge check

Which OSI layer handles IP addresses and routing?