Zero-Knowledge (ZK) Proofs are proofs that reveal no information except the fact that the claimed statement is true. For example, they can be used to prove that you know the password to your email account, without revealing your password to the server. They can also be used to prove that you are the owner of some biometric information, without you having to reveal your (highly sensitive!) biometric information to anyone else. ZK proofs are used to design secure multi-party computation protocols, efficient algorithms on the blockchain, and much more.