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Course details

Cyber Security

Learn the foundations of defensive security: how computers, operating systems and networks work, the core ideas like the CIA triad and defence in depth, and how to protect accounts, data and people. Every lesson helps one small bookshop stay safe.

Ready to learn6 sections · 24 lessons
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Course curriculum

IT Foundations for Security3 lessons

Meet Hollow Oak Books and the equipment you will protect. Learn where data lives inside a computer, how devices talk without wires, and how to fix problems without weakening security.

  1. Where Data Lives in a Computer12 min
  2. Wireless Connections and Their Reach12 min
  3. Troubleshooting Without Weakening Security12 min
Operating Systems for Security3 lessons

Windows, macOS and Linux look different but guard the same things. Learn to set permissions with least privilege and to install and update software without inviting trouble in.

  1. Windows, macOS and Linux: Same Jobs, Different Doors12 min
  2. Permissions and Least Privilege12 min
  3. Installing Software and Keeping It Updated12 min
Networking for Defenders5 lessons

Learn the layers data passes through, how addresses, DNS and DHCP work, which ports carry which services, and what TLS really promises, always asking where a defender should stand.

  1. The OSI Model: Seven Layers to Guard15 min
  2. Public and Private IP Addresses15 min
  3. DNS and DHCP: The Network's Phone Book and Receptionist12 min
  4. Common Ports and Protocols12 min
  5. SSL and TLS Basics15 min
Core Security Principles4 lessons

Learn the CIA triad, how to weigh risk, why defences come in layers and separated zones, and what zero trust changes about who gets in. These ideas guide every decision in the rest of the course.

  1. The CIA Triad12 min
  2. Understanding Risk15 min
  3. Defence in Depth and Network Segmentation15 min
  4. Core Concepts of Zero Trust12 min
Identity, Access and Cryptography4 lessons

Separate authentication from authorisation, add a second factor, see why passwords are stored as salted hashes, and understand how public and private keys make TLS and certificates work.

  1. Authentication vs Authorisation12 min
  2. MFA and 2FA12 min
  3. Hashing and Salting Passwords15 min
  4. Public Keys, Private Keys and Certificates15 min
Common Threats and How to Defend5 lessons

Spot social engineering, understand the main kinds of malware, defend accounts against password guessing, build backups that survive ransomware, and follow a calm runbook when an incident happens.

  1. Phishing and Social Engineering12 min
  2. How Malware Works and Its Main Types12 min
  3. Brute Force vs Password Spraying12 min
  4. Backups and Resiliency12 min
  5. Incident Response Runbooks15 min