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Module 4~9 min

Introduction to Encryption

Encryption is one of the fundamental tools that protects information as it's stored or sent across a network.

What You'll Learn

  • What encryption does
  • The basic idea of a key
  • Why encryption matters for confidentiality

Scrambling Information

Encryption transforms readable information (plaintext) into an unreadable form (ciphertext) using a mathematical process, protecting it from anyone who doesn't have the means to reverse the transformation.

Keys

A key is the piece of information needed to encrypt or decrypt data. Without the correct key, ciphertext should be practically impossible to turn back into readable information.

Example

When a website uses HTTPS, it uses encryption so that even if someone intercepts the traffic, they see only unreadable ciphertext rather than your actual data.

Key Concepts

EncryptionPlaintextKey

Key Takeaways

  • Encryption transforms readable data into unreadable ciphertext
  • A key is required to encrypt or decrypt the data
  • Encryption protects the confidentiality of stored and transmitted data

Knowledge Check

What is encrypted, readable data called before it's transformed?

What is encrypted, readable data called before it's transformed?