Will Fedimints Bring Bitcoin To The World? – Bitcoin Magazine

I. E-Cash Strikes Back

Thirty three years ago, the computer scientist David Chaum launched e-cash, a new way for people to spend digital dollars without revealing their personal information.

Users plugged their bank card into a terminal to deposit traditional digital dollars into Chaum’s bank — called DigiCash — which issued in return e-cash IOU tokens called “cyberbucks.” These tokens were bearer instruments, and could be traded privately across the internet between different e-cash users or spent on, for example, articles from “Encyclopedia Britannica.” When merchants redeemed the tokens in exchange for dollar deposits in their bank accounts, DigiCash was not able to link the redemption to the original deposit, thanks to a clever cryptographic concept Chaum invented called blind signatures.



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