Cryptography Foundations — How Encryption Works

A gentle, jargon-free beginner's course on how cryptography actually works. Follow a secret message from Alice to Bob — past Eve, the eavesdropper — and build up encryption, keys, public keys, hashing, signatures, and trust one everyday analogy at a time, until the padlock in your browser makes complete sense. Four gentle activities in every lesson.

What you'll learn

• Understand the three things cryptography protects: secrecy, integrity, and authenticity.
• Explain encryption and keys, and how public keys let strangers share secrets safely.
• Explain hashing (fingerprints) and digital signatures in plain language.
• Understand certificates, the browser padlock, and everyday encryption — and use it wisely.

Sign in to enrol — you can pay by bKash or Nagad, or apply a promo code.