Keeping Information Secret

Encryption transforms readable data into a coded form that only someone with the right key can understand. This keeps information safe, even if it's intercepted.

How Encryption Works

• Plaintext: The original, readable data.
• Ciphertext: The scrambled, unreadable version.
• Key: A special code needed to turn ciphertext back into plaintext.

Formula:
Encryption can be represented as \( C = E(P, K) \), where \( C \) is ciphertext, \( P \) is plaintext, \( K \) is the key, and \( E \) is the encryption function.

Types of Encryption

• Symmetric: The same key is used to encrypt and decrypt.
• Asymmetric: Uses a public key to encrypt and a private key to decrypt.

Data Protection Practices

• Encrypt data at rest and in transit.
• Back up important data.
• Manage encryption keys securely.

Real-World Applications

• Messaging apps use end-to-end encryption so only you and your friend can read your chats.
• Online shopping sites encrypt your credit card details during checkout.