Digital currencies like bitcoin are touted for their anonymity. But in practice, it can be possible to trace transactions across the shared bitcoin ledger known as the blockchain and figure out who's sending bitcoin to whom.
The creators of a new bitcoin alternative dubbed Zcash say that currency—currently in pre-release alpha testing—will make that identification effectively impossible. Zcash will rely on algorithms known as zero-knowledge proofs that will allow users to prove they actually have the money they're sending, without needing to reveal their identities or how much they're sending at any given time.
"Unlike bitcoin, Zcash transactions automatically hide the sender, recipient, and value of all transactions on the blockchain," according to the Zcash website. "Only those with the correct view key can see the contents. Users have complete control and can opt in to provide others with their view key at their discretion."
http://www.fastcompany.com/3056474/new-bitcoin-rival-currency-will-offer-more-anonymity-say-its-creators