One-time pad
From Network Dictionary Wiki
In cryptography, a one-time pad is a system in which a private key generated randomly is used only once to encrypt a message that is then decrypted by the receiver using a matching one-time pad and key. Messages encrypted with keys based on randomness have the advantage that there is theoretically no way to "break the code" by analyzing a succession of messages.
Note: This article is a stub. We welcome reader's contributions to make it an informative article for other readers.