Cybersecurity I – SS1 Digital Technologies Lesson Note (Second Term)

Cybersecurity is the practice of protecting computers, smartphones, networks and data from digital attacks and unauthorised access.

Behavioural objectives

By the end of the lesson, students should be able to:

1. define cybersecurity and give reasons why it is important;
2. describe four common types of malware: viruses, Trojans, ransomware and spyware;
3. explain how phishing works and identify its red flags;
4. state the difference between black hat and ethical hackers and list ways hackers get into systems;
5. apply basic safety habits to protect their devices and accounts.

What is cybersecurity?

Cybersecurity is the “digital fence” that keeps our computers, smartphones, networks and data safe from attack.

• Physical world: we use locks on doors, fences around houses and security guards at the bank.
• Digital world: we use passwords, antivirus software, updates and careful habits.
• What it protects: devices, networks, accounts and the data stored on them.
• What it guards against: digital attacks and unauthorised access.

Why is cybersecurity important?

Cybersecurity is important because most daily activities now happen online and stolen data can cause real harm.

• Everyday use: we chat on WhatsApp, check school results on websites and use banking apps like OPay or Kuda.
• Protecting personal privacy: strangers should not read your private chats or see your private photos.
• Preventing financial loss: hackers can steal money if they get access to banking details.
• National security: governments store secret information online, and if it is stolen, a whole country could be at risk.

What is malware?

Malware, short for “malicious software”, is a program designed to damage, disrupt or steal data.

• Simple picture: it is like a biological virus that makes a person sick, but it attacks a computer.
• How it spreads: through flash drives, email attachments, unsafe downloads and fake apps.

What are the common types of malware?

There are four common types of malware: viruses, Trojans, ransomware and spyware.

1. Viruses: they “infect” other files and spread when you share those files, for example by flash drive or email.
2. Trojans: named after the “Trojan Horse” from history, a Trojan looks like a harmless game or app but “opens the gates” for hackers once installed.
3. Ransomware: this is like digital kidnapping, because it locks your files and demands money (a ransom) to give them back.
4. Spyware: it hides in the background and watches what you do, including the passwords you type.

What is the difference between a virus and a Trojan?

• Virus: a malicious program that attaches itself to other files and spreads when files are shared.
• Trojan: a malicious program that pretends to be a useful or harmless app to trick you into installing it.

What is phishing?

Phishing is a trick in which a hacker sends a fake message to make you give away personal details.

• Why the name: it sounds like “fishing”.
• The lure: a fake email or SMS.
• The bite: a victim who clicks the link or replies with their details.

How does phishing work?

1. You get an email that looks exactly like it is from your bank or a social media site.
2. It says something like: “Your account has been blocked! Click here to verify your identity.”
3. The link takes you to a fake website that looks 100% real.
4. You type in your username and password.
5. You have handed your details directly to the hacker.

What are the red flags of phishing?

• Urgent language: the sender tries to scare you with words like “Immediately” or “Account suspended”.
• Bad grammar: many phishing emails have spelling mistakes.
• Strange links: if you hover over the link, the address looks slightly “off”, for example faceb00k.com instead of facebook.com.
• Too-good-to-be-true offers: messages that say you won money or a prize from a company you do not know.
• Requests for private details: messages that ask for your password, PIN or verification code.

What should you do when you get a suspicious message?

1. Do not click the link or open any attachment.
2. Do not reply or give any personal details.
3. Check with the real company using its official website or phone number.
4. Delete the message, and tell a parent, teacher or guardian.

What is hacking?

Hacking is the act of identifying and exploiting weaknesses in a computer system or network to gain unauthorised access.

Who are the hackers?

There are two main groups of hackers: black hat hackers and ethical (white hat) hackers.

• Black hat hackers: these are the criminals, who break into systems to steal money, delete data or cause chaos.
• Ethical hackers (white hat): these are the “good guys”, paid by companies to try to break into their systems and find the holes.

How do hackers get in?

• Weak passwords: using “123456” or your birthdate is like leaving your front door wide open.
• Unsecured Wi-Fi: public Wi-Fi in cafes or parks is often easy for hackers to “eavesdrop” on.
• Software holes: if you do not update your phone or apps, old “holes” stay open for hackers to use.
• Tricking users: phishing messages and fake apps make people open the door themselves.

Why are humans called the weakest link in cybersecurity?

Humans are called the weakest link because many attacks succeed through human mistakes, not through broken technology.

• Clicking links: a person clicks a phishing link without checking it.
• Weak passwords: a person picks an easy password or uses the same one everywhere.
• Sharing codes: a person gives out a PIN or verification code to a stranger.
• Ignoring updates: a person delays updates, leaving security holes open.

How can students stay safe online?

Students stay safe online by following a simple safety checklist, because hackers keep changing their methods.

1. Strong passwords: use a mix of letters, numbers and symbols, for example a pattern like Blue!Sky#26 (make your own, do not copy this one).
2. Two-factor authentication (2FA): the app asks for a code sent to your phone after you type your password, which adds an extra layer of protection.
3. Do not click random links: if an offer seems too good to be true, like “Win a free iPhone”, it is probably a scam.
4. Keep software updated: when your phone says “Update available”, do it, because updates usually include security fixes.
5. Use antivirus software: it detects and removes malware from your device.
6. Be careful on public Wi-Fi: avoid banking or entering passwords on open networks.
7. Keep passwords private: never share your password or verification codes with anyone.

Evaluation

1. In your own words, what is the difference between a “virus” and a “Trojan”?
2. Imagine you get an SMS saying you won ₦50,000 from a company you don’t know. What should you do?
3. Why do we say that “humans” are often the weakest link in cybersecurity?
4. What is the difference between an “ethical hacker” and a “black hat hacker”?

Assignment

Write a short note that lists the four types of malware with a one-sentence explanation of each, then choose any three items from the student’s safety checklist and say how each one protects you from hackers.