5.3

Security

Cambridge IGCSE Computer Science (0478)  · Unit 5: The internet and its uses  · 10 flashcards

Security is topic 5.3 in the Cambridge IGCSE Computer Science (0478) syllabus , positioned in Unit 5 — The internet and its uses , alongside Networks and The Internet.  In one line: 'Malware' is any software intentionally designed to cause damage to a computer, server, client, or computer network. Examples include viruses, worms, Trojans, and ransomware.

This topic is examined in Paper 1 (computer systems theory) and Paper 2 (algorithms, programming and logic).

The deck below contains 10 flashcards — 8 definitions and 2 key concepts — covering the precise wording mark schemes reward.  Use the 8 definition cards to lock down command-word answers (define, state), then move on to the concept and application cards to handle explain, describe and compare questions.

Key definition

The term 'malware' and give two examples

'Malware' is any software intentionally designed to cause damage to a computer, server, client, or computer network. Examples include viruses, worms, Trojans, and ransomware.

What the Cambridge 0478 syllabus says

Official 2026-2028 spec

These are the exact learning objectives Cambridge sets for this topic. Match the command word (Describe, Explain, State, etc.) in your answer to score full marks.

  1. Describe Describe the processes involved in, and the aim of carrying out, a range of cyber security threats including brute-force attack, data interception, DDoS attack, hacking, malware (virus, worm, Trojan horse, spyware, adware, ransomware), pharming, phishing, social engineering
  2. Explain Explain how a range of solutions are used to help keep data safe from security threats including access levels, anti-malware, authentication, automating software updates, checking spelling and tone of communications, checking URLs, firewalls, privacy settings, proxy-servers, SSL security protocol
Definition Flip

Define the term 'malware' and give two examples.

Answer Flip

'Malware' is any software intentionally designed to cause damage to a computer, server, client, or computer network. Examples include viruses, worms, Trojans, and ransomware.

Key Concept Flip

Explain the difference between a virus and a worm.

Answer Flip

A virus requires a host program to infect and spread, while a worm is a self-replicating program that can spread independently across a network without needing a host. Worms exploit vulnerabilities to self-propagate, often causing network congestion.

Definition Flip

Describe what a Trojan horse is and how it deceives users.

Answer Flip

A Trojan horse disguises itself as legitimate software to trick users into installing it. Once installed, it can perform malicious actions like stealing data, installing other malware, or granting unauthorized access to the system.

Definition Flip

What is spyware and what are its potential consequences?

Answer Flip

Spyware is software that secretly monitors and collects user information, such as browsing history, passwords, and financial details. It can lead to identity theft, financial loss, and compromised privacy.

Definition Flip

Explain what ransomware is and how it affects a user's data.

Answer Flip

Ransomware is a type of malware that encrypts a victim's files, making them inaccessible until a ransom is paid to the attacker. It can cripple businesses and individuals by holding their data hostage.

Definition Flip

Describe the technique of 'phishing' and give an example.

Answer Flip

Phishing involves deceiving users into revealing sensitive information, such as usernames, passwords, and credit card details, by disguising as a trustworthy entity in an electronic communication. An example is an email pretending to be from a bank asking you to update your account details.

Definition Flip

What is a firewall and how does it enhance computer security?

Answer Flip

A firewall is a network security system that monitors and controls incoming and outgoing network traffic based on predetermined security rules. It helps protect a network from unauthorized access, malware, and other cyber threats.

Definition Flip

Explain the purpose of authentication and describe two methods used to authenticate users.

Answer Flip

Authentication verifies the identity of a user or device attempting to access a system or network. Two common methods are password authentication (using a secret word or phrase) and biometric authentication (using unique biological traits like fingerprints).

Key Concept Flip

What is two-factor authentication (2FA) and why is it more secure than single-factor authentication?

Answer Flip

Two-factor authentication requires users to provide two different types of authentication factors (

Example: password and a code sent to their phone), adding an extra layer of security compared to single-factor authentication (. password only), making it harder for attackers to gain unauthorized access.
Definition Flip

Describe the purpose and importance of creating regular data backups.

Answer Flip

Data backups involve creating copies of important data to be stored separately from the original source. This provides a safety net in case of data loss due to hardware failure, malware attacks, human error, or natural disasters, allowing for data restoration and minimizing downtime.

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5.2 The Internet 6.1 Automated systems

Key Questions: Security

Define the term 'malware' and give two examples.

'Malware' is any software intentionally designed to cause damage to a computer, server, client, or computer network. Examples include viruses, worms, Trojans, and ransomware.

Describe what a Trojan horse is and how it deceives users.

A Trojan horse disguises itself as legitimate software to trick users into installing it. Once installed, it can perform malicious actions like stealing data, installing other malware, or granting unauthorized access to the system.

What is spyware and what are its potential consequences?

Spyware is software that secretly monitors and collects user information, such as browsing history, passwords, and financial details. It can lead to identity theft, financial loss, and compromised privacy.

Explain what ransomware is and how it affects a user's data.

Ransomware is a type of malware that encrypts a victim's files, making them inaccessible until a ransom is paid to the attacker. It can cripple businesses and individuals by holding their data hostage.

Describe the technique of 'phishing' and give an example.

Phishing involves deceiving users into revealing sensitive information, such as usernames, passwords, and credit card details, by disguising as a trustworthy entity in an electronic communication. An example is an email pretending to be from a bank asking you to update your account details.

More topics in Unit 5 — The internet and its uses

Security sits alongside these Computer Science decks in the same syllabus unit. Each uses the same spaced-repetition system, so progress in one informs the next.

Cambridge syllabus keywords to use in your answers

These are the official Cambridge 0478 terms tagged to this section. Mark schemes credit responses that use the exact term — weave them into your answers verbatim rather than paraphrasing.

malware virus worm Trojan spyware ransomware phishing firewall authentication password biometric two-factor backup

Key terms covered in this Security deck

Every term below is defined in the flashcards above. Use the list as a quick recall test before your exam — if you can't define one of these in your own words, flip back to that card.

The term 'malware' and give two examples
Describe what a Trojan horse is and how it deceives users
Spyware and what are its potential consequences
Explain what ransomware is and how it affects a user's data
Describe the technique of 'phishing' and give an example
Firewall and how does it enhance computer security
Explain the purpose of authentication and describe two methods used to authenticate users
Describe the purpose and importance of creating regular data backups

How to study this Security deck

Start in Study Mode, attempt each card before flipping, then rate Hard, Okay or Easy. Cards you rate Hard come back within a day; cards you rate Easy push out to weeks. Your progress is saved in your browser, so come back daily for 5–10 minute reviews until every card reads Mastered.