Bitcoin is a successful implementation that combines other algorithms and technologies into one network. Satoshi looked at existing creations and designed a well-oiled machine. Bitcoin uses digital signatures, cryptography, hash functions, Proof of Work, merkle trees, etc. There might be other ways to create decentralized digital money, but this is what satoshi threw into the melting pot. A decade later and the experiment still works.
Satoshi Nakamoto is genius, truly, and created a Protocol that gives power to decentralized community to develop and make it better with time. From ideas to works, practice, Satoshi Nakamoto did many great things for us. His disappearance is a great gift for us too as if he is known, and get arrested by government similarly to TON CEO Pavel Durov, who knows what will happen with Bitcoin.
eCash and B-money the earliest cryptocurrency crawled so that Bitcoin can fly.
There are more than e-Cash and B-money before Bitcoin. The prehistory has names of cryptocurrencies created before Bitcoin.
1989 with DigiCash
1994 with CyberCash
1996 with E-Gold
1997 with HashCash
1998 with Bit Gold and B-Money
2001 with BitTorrent