In cryptography, "zero knowledge" means something very different than "service providers cannot access cleartext data". > In cryptography, a zero-knowledge pro

In cryptography, "zero knowledge" means something very different than "service providers cannot access cleartext data". > In cryptography, a zero-knowledge proof or zero-knowledge protocol is a method by which one party (the prover) can prove to another party (the verifier) that a given statement is true, without conveying any information apart from the fact that the statement is indeed true. source: https://en.wikipedia.org/wiki/Zero-knowledge_proof https://en.wikipedia.org/wiki/Zero-knowledge_proof z.cash is a zero knowledge system and has a good definition of it on its FAQ: > Zero knowledge proofs are a scientific breakthrough in the field of cryptography: they allow you to prove knowledge of some facts about hidden information without revealing that information. The property of allowing both verifiability and privacy of data makes for a strong use case in all kinds of transactions, and we’re integrating this concept into a block chain for encrypting the sender address, the recipient address, and the amount. A block chain that encrypts transaction data (making it private) and lacks zero-knowledge proofs also lacks the assurance that all the transactions are valid. This is because the nodes in the network can’t determine whether the sender really had that money or whether they previously sent it to someone else, or never had it in the first place. The encrypted data becomes unverifiable by network nodes. source: https://z.cash/support/faq.html?page=0 https://z.cash/support/faq.html?page=0