## Zero-Knowledge Proofs

A zero-knowledge proof is a type of verification that takes place between a prover and a verifier. It is also frequently referred to as a zk protocol. In a system of proof with zero knowledge, the prover can demonstrate to the verifier that they are aware of a specific piece of knowledge (such as the answer to a mathematical problem) without disclosing the information itself. Modern cryptographers can leverage these proof systems to offer higher levels of security and privacy. In a 1985 MIT study written by Shafi Goldwasser and Silvio Micali, the idea of a zero-knowledge proof was originally introduced. They showed that it was feasible to prove some mathematical features of a number without revealing the number or any other details about it. The mathematically important discovery that interactions between a prover and a verifier could lessen the amount of data needed to prove a specific theorem was also presented in this study. Completeness and soundness are two fundamental characteristics that a zk proof must satisfy. The ability of the prover to demonstrate knowledge of the pertinent material to a high degree of likely accuracy is referred to as completeness. The verifier must be able to conclusively verify whether the prover is in fact in possession of the information for the proof to be considered valid. The proof must be successful in achieving both completeness and soundness without the information in question ever being shared between the prover and the verifier in order to be truly zero-knowledge. Zero-knowledge proofs are typically employed in applications where security and privacy are crucial. Zk proofs, for instance, can be used by authentication systems to validate credentials or identities without actually disclosing them. It can be used, for instance, to confirm that someone has a password for a computer system without revealing the password itself. The realm of cryptocurrencies and blockchain technology is one well-known real-world use of zero-knowledge proofs. Blockchain transactions can now be conducted more privately thanks to privacy-focused cryptocurrencies like Zcash, which use a proof type called a zero-knowledge Succinct Non-interactive Argument of Knowledge (zk-SNARK). Since its Byzantium version in 2017, Ethereum has been working with zk-SNARK proofs as well.