Computing

🛡 Section A: Cybersecurity

🔐 1. Brute Force Attacks

  • Example: A hacker trying to guess a 4-digit phone lock by trying 1234, 1111, 4321, etc., until it works.

  • It’s slow, but works if your password is easy!

🔒 How to stay safe:

  • Use longer, complex passwords like C@ts4Life!2025

  • Use two-factor authentication (like getting a code on your phone)

📜 2. Encryption – Caesar Cipher

  • It's a type of substitution cipher – replaces each letter with another one a fixed number of spaces away.

Caesar Cipher Example (shift 4):

  • Message: CHAT

  • Ciphered: GLEX

    • C → G

    • H → L

    • A → E

    • T → X

Another Example (shift 1):

  • Message: ZEBRA

  • Ciphered: AFCSB

/

🎭 3. Social Engineering

Type

Example

Phishing

You get an email from "your bank" asking you to click a link and enter your password

Pretexting

Someone calls pretending to be IT support asking for your login details

Baiting

A USB drive is left in a public place labeled "Confidential – Pay Info"

Tailgating

Someone follows you into a secure area by pretending they forgot their pass

🤖 Section B: Machine Learning & AI Ethics

🤖 1. Machine Learning

Example 1: Spam Filter

  • Looks at emails and learns which ones are spam based on keywords like "Win now!", "Free prize!", etc.

  • Learns from examples: some spam, some not.

Example 2: Movie Recommendations

  • Based on what you’ve watched, it suggests what you might like next (like on Netflix or YouTube).

What ML Code Might Look Like:
from sklearn.tree import DecisionTreeClassifier

data = [[5, 100], [3, 75], [10, 150]]  # hours studied, marks
labels = ["Pass", "Fail", "Pass"]

model = DecisionTreeClassifier()
model.fit(data, labels)

print(model.predict([[4, 90]]))  # → Predicts Pass or Fail

  • An AI that sorts CVs but ignores women applicants – is that ethical?

  • A robot in a hospital makes decisions about patient treatment – who is responsible if it makes a mistake?

👩‍💻 Section C: Reading Python Code

🔁 1. Loops

For loop Example:
for number in range(1, 6):
    print("You are on level", number)

Output:

You are on level 1
You are on level 2
You are on level 3
You are on level 4
You are on level 5
While loop Example:
x = 1
while x <= 3:
    print("Try number", x)
    x += 1

🔍 2. IF Statements

Example 1:
age = 15
if age >= 13:
    print("You can sign up!")
else:
    print("Sorry, you're too young.")
Example 2 (with multiple conditions):
score = 80
if score >= 90:
    print("Grade: A")
elif score >= 70:
    print("Grade: B")
else:
    print("Grade: C or below")

🎮 3. Events and Collisions (often in games!)

Example Event:
if key_pressed == "space":
    jump()

This means the game checks if the spacebar is pressed. If yes, the character jumps.

Example Collision:
if player_rect.colliderect(enemy_rect):
    health -= 1

If the player touches (collides with) the enemy, their health goes down.

Example of a game loop:
while game_running:
    check_events()
    move_player()
    check_collisions()
    update_screen()