What does end-to-end encryption mean in messaging apps?

What does end-to-end encryption mean in messaging apps?

• A. It means messages are read by the service provider.
• B. It means messages are encrypted only during transit, not end-to-end.
• C. It means only the communicating users can read the messages; even the service provider cannot decrypt them.
• D. It means messages are stored in the cloud unencrypted.

Answer: (C)

End-to-end encryption means that only the devices of the people chatting can read the messages. The app encrypts each message on the sender’s device and it can only be decrypted on the recipient’s device, using keys that stay on the devices themselves. Because the service provider only handles encrypted data and doesn’t hold the private keys, they can’t read the content of the messages—even though they may still see metadata like who is talking to whom and when. This is different from encryption that protects content only while it’s moving between devices; in that case, the provider could access the message content once it’s stored or processed on their servers. It’s also not about storing unencrypted messages in the cloud.

End-to-end encryption means that only the devices of the people chatting can read the messages. The app encrypts each message on the sender’s device and it can only be decrypted on the recipient’s device, using keys that stay on the devices themselves. Because the service provider only handles encrypted data and doesn’t hold the private keys, they can’t read the content of the messages—even though they may still see metadata like who is talking to whom and when. This is different from encryption that protects content only while it’s moving between devices; in that case, the provider could access the message content once it’s stored or processed on their servers. It’s also not about storing unencrypted messages in the cloud.