source: danheld.comMost people think that Bitcoin was created in 2009, but story of Bitcoin is much bigger and it goes 40 years back in history.
We started back in long time ago year 1974 and important events are presented in above tree image presentation.
40 years of research, development and demand:
1974 Cerf and Kahn ''A Protocol for Pocket Network Intercommunication'' TCP/IP
https://en.wikipedia.org/wiki/Internet_protocol_suite1976 Whitfield Diffie & Martin Hellman ''New Directions in Cryptography''
https://ee.stanford.edu/~hellman/publications/24.pdf1978 RSA Public Key Cryptosystems
https://en.wikipedia.org/wiki/RSA_(cryptosystem)
1980 Ralph Merkle ''Protocols for Public Key Cryptosystems''
http://www.merkle.com/papers/Protocols.pdf1983 David Chaum ''Blind Signatures for Untraceable Payments''
https://sceweb.sce.uhcl.edu/yang/teaching/csci5234WebSecurityFall2011/Chaum-blind-signatures.PDF1985 Elliptic Curve Cryptography
https://en.wikipedia.org/wiki/Elliptic-curve_cryptography1988 Timothy C. May ''The Crypto-Anarchist's Manifesto''
https://www.activism.net/cypherpunk/crypto-anarchy.html1989 David Chauman ''Founded DigiCash''
https://en.wikipedia.org/wiki/DigiCash1991 Phil Zimmermann ''Pretty Good Privacy'' PGP
https://en.wikipedia.org/wiki/Phil_Zimmermann1992 Cypherpunk founded in SF by Eric Hughes, Zimothy C.May and John Gilmore
https://en.wikipedia.org/wiki/Cypherpunk1994 CyberCash
https://en.wikipedia.org/wiki/CyberCash1994 Timothy C. May ''The Cyphernomicon''
https://nakamotoinstitute.org/static/docs/cyphernomicon.txt1996 E-Gold
https://en.wikipedia.org/wiki/E-gold1996 NSA, ''How To Make A Mint''
http://groups.csail.mit.edu/mac/classes/6.805/articles/money/nsamint/nsamint.htm1997 Adam Back, HashCash, DOS counter-measure w/ proof-of-fork
https://en.wikipedia.org/wiki/Adam_Back1997 Nick Szabo ''Formalizing and Securing Relationships on Public Networks''
https://ojphi.org/ojs/index.php/fm/article/view/548/4691998 Nick Szabo ''Securing Property Titles with Owner Authority''
https://nakamotoinstitute.org/secure-property-titles/1998 Bit-Gold
https://en.wikipedia.org/wiki/Nick_Szabo1998 Wei Dai ''B-Money'' - decentralized database to record txs and using a type of proof-of-work
https://en.bitcoin.it/wiki/B-money1998-2001 Many onle retailer currencies in the bottom (Beenz, Floor etc)
https://en.wikipedia.org/wiki/Dot-com_bubble2001 Bram Cohen, BitTorrent
https://en.wikipedia.org/wiki/Bram_Cohen2001 Distributed Hash Tables, Video game currencies and markets era started
https://en.wikipedia.org/wiki/Distributed_hash_table2004 Hal Finney ''Reusable Proof-of-Work''
https://nakamotoinstitute.org/finney/rpow/index.html2006 Liberty reserve
https://en.wikipedia.org/wiki/Dot-com_bubble 2008 Bitcoin Launched Whitepaper
https://bitcoin.org/bitcoin.pdf