Secure conversations: How end-to-end encryption keeps your messages private

 Definition

Encryption is the process of converting information (plaintext) into a secret code (ciphertext) using a mathematical algorithm and a key, so that only authorized people can read it.

How it works

Plaintext → (Encryption algorithm Key) → Ciphertext

Ciphertext → (Decryption algorithm Key) → Plaintext

How encryption helps in privacy

• Prevents unauthorised access: Even if data is stolen, it remains unreadable without the key
• Protects sensitive information: Like passwords, bank details, personal messages
• Ensures confidentiality: Only the intended person can read the message
• Builds trust in digital systems: Online banking, e-commerce, and messaging apps rely on encryption

End-to-end encryption (E2EE)

End-to-End Encryption ensures that a message is encrypted on the sender’s device and only decrypted on the receiver’s device. No third party—including service providers, hackers, or even the app company—can read the data in between.

 How it works

1. Sender’s device encrypts the message with a unique key
2. Message travels through the internet in encrypted form.
3. Only the receiver’s device has the matching decryption key.
4. Even the messaging service (e.g., WhatsApp, Signal) cannot read it.

Importance

• Protects privacy in digital communication
• Prevents surveillance or misuse of personal conversations
• Essential for human rights, journalism, and secure commerce

 Answer in exam format (short notes)

1. Encryption: A security technique that converts data into unreadable form (ciphertext) using algorithms and keys. Ensures only authorized users can access data.
2. Role in privacy: Safeguards personal and financial information from unauthorized access, maintaining confidentiality and trust.
3. End-to-end encryption: A method where data is encrypted at the sender’s end and decrypted only at the receiver’s end, preventing even service providers from reading the communication.