Chaum's blind signatures

Chaum's blind signatures are a cryptographic technique that allows someone to get a message signed by a signer without revealing the message's content. Imagine placing a document inside a "blind" envelope that encrypts it, so the signer can sign it without seeing the actual content. Once signed, the sender removes the "blind," revealing a signature that is valid but doesn’t reveal the message's original details. This process ensures privacy and anonymity, making it useful for secure voting, digital cash, and privacy-preserving transactions.