Encryption

Cryptography 🔒 • Security+ 🏆 Difficulty: free

Definition

Encryption converts readable data (plaintext) into unreadable data (ciphertext) so only someone with the correct key can recover the original content.

Examples

  • A website uses TLS so login details are encrypted in transit and cannot be read over public Wi-Fi.
  • A laptop with full-disk encryption keeps files protected if the device is lost or stolen.

Discover 🔎

Encryption protects confidentiality and, when used with the right modes, also protects integrity. It is used in two main places: data in transit (across networks) and data at rest (on disks, databases, backups). The core idea is simple: without the correct key, intercepted data is useless.

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