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There is currently a surge in popularity among many of the biggest public blockchains around the implementation of zero knowledge protocols, most commonly zk-SNARK, or Zero-Knowledge Succinct Non-Interactive Argument of Knowledge proofs. Zero-knowledge proofs add a considerable layer of privacy to public blockchains, and do not reveal the transaction histories of those sending funds, as public blockchains do currently. As of writing, several of the most prominent currencies are discussing adoption of zk-SNARKs, including Cardano, Tron, Tezos and perhaps most notably Ethereum.