He introduced the concept digital cash on basis of blind signature and group signatures, a form of basic decentralised ledger which is the basis of Blockchain today..
Satoshi created blockchain.
There has been digital money in the past, but they all failed. Satoshi Nakamoto makes it in a way it would not be centralized like those of the past that failed, he made it dlto be decentralized.
Please add the source for a better understanding. I know a couple of people or groups of people have tried to create digital cryptocurrency but not succeed. I might be wrong but that's what I know. Satoshi is the first person who succeeded to create digital currency through Blockchain technology which is called Blockchain.
I he no talking more than digicash and all old form of money that failed until Satoshi created bitcoin.