Marc Andreessen, the developer of the graphical web browser NCSA Mosaic, believes that at a fundamental level, the Bitcoin system is a breakthrough in computer science, built on 20 years of research into "electronic cash" and 40 years of work in cryptography by thousands of researchers around the world.
In 1983, David Chaum and Stefan Brands proposed the first protocols for "electronic cash."
In May 1997, Adam Back proposed Hashcash to counteract spam and DoS attacks, based on a proof-of-work system. Subsequently, a similar system in another implementation became part of the procedure for creating new blocks in the Bitcoin base.
The ideas of the cryptocurrency "b-money" were described in 1998 by Wei Dai in a mailing list of cypherpunks. Independently, around the same time, similar ideas were proposed by Nick Szabo for "bit-gold." Nick Szabo also proposed a market mechanism model based on inflation management and explored some aspects of reliable information detection in an unreliable decentralized system (the Byzantine generals problem).
Later, Hal Finney implemented a connection of hash block chains for the Hashcash system based on an IBM encryption chip as part of the TPM specification. Hal Finney became the second participant in the Bitcoin network.
On August 18, 2008, the domain bitcoin.org was registered. On October 31, 2008, in a mailing list dedicated to cryptography, a person or group of people under the pseudonym Satoshi Nakamoto published a link to the white paper titled "Bitcoin: A Peer-to-Peer Electronic Cash System" — a concise description of the protocol and the principle of operation of the payment system in the form of a peer-to-peer network.
On January 3, 2009, the first block was generated, for which the first reward of 50 bitcoins was credited, and the source code of the client program was published. The first transaction of bitcoin transfer occurred on January 12, 2009 — Satoshi Nakamoto sent Hal Finney 10 bitcoins. The first exchange of bitcoins for national currency occurred in September 2009 — Martti Malmi sent the user with the pseudonym NewLibertyStandard 5050 bitcoins, for which he received $5.02 in his PayPal account. NewLibertyStandard proposed using the cost of electricity spent on generation to estimate the value of bitcoins.
The first exchange of bitcoins for real goods took place on May 22, 2010 — American Laszlo Hanyecz received two pizzas delivered for 10,000 bitcoins.
Further development is organized and coordinated by the community of developers, with any significant changes to the protocol requiring acceptance by the majority of mining pool owners.
On August 1, 2017, a group of developers and miners launched a fork of Bitcoin called Bitcoin Cash. The new cryptocurrency has a shared history with Bitcoin: backward compatibility of the block structure until August 1, but has an incompatible structure after August 1.
