Before the release of Bitcoin, there were several digital cash technologies starting with ecash technology by mathematician David Chaum in 1987, which is electronic money based on cryptographic protocols. Stefan Brands. In 1997, Adam Back developed the hashcash technology, a proof of work to combat spam. Between 1998-2005, Wei Dai launched the idea of decentralized cryptography. Nick Szabo developed the 'bit gold' project, a digital currency based on decentralization using many elements found in Bitcoin, and this system faced a strong attack.
There was a lot of speculation about the identity of Satoshi Nakamoto with suspects including Wei Dai and Hal Finney. There were also some rumors about the possibility that Satoshi Nakamoto was working in the European financial sector.
