In cryptography

Cryptography

Cryptography is the practice and study of techniques for secure communication in the presence of third parties...

, a zero-knowledge proof or zero-knowledge protocol is an interactive method for one party to prove to another that a (usually mathematical) statement is true, without revealing anything other than the veracity of the statement.
There is a well-known story presenting some of the ideas of zero-knowledge proofs, first published by Jean-Jacques Quisquater

Jean-Jacques Quisquater

Jean-Jacques Quisquater is a cryptographer and a professor at Université catholique de Louvain.-External links:*...

 and others in their paper "How to Explain Zero-Knowledge Protocols to Your Children".