Bitcoin Gold (BTG) is a

cryptocurrency A cryptocurrency, crypto-currency, or crypto is a digital currency designed to work as a medium of exchange through a computer network that is not reliant on any central authority, such as a government or bank, to uphold or maintain it. It i ...

. It is a hard fork of

Bitcoin Bitcoin (abbreviation: BTC; sign: ₿) is a decentralized digital currency that can be transferred on the peer-to-peer bitcoin network. Bitcoin transactions are verified by network nodes through cryptography and recorded in a public distr ...

, the

open source Open source is source code that is made freely available for possible modification and redistribution. Products include permission to use the source code, design documents, or content of the product. The open-source model is a decentralized so ...

. It is an open source, decentralized

digital currency Digital currency (digital money, electronic money or electronic currency) is any currency, money, or money-like asset that is primarily managed, stored or exchanged on digital computer systems, especially over the internet. Types of digital cu ...

without a

central bank A central bank, reserve bank, or monetary authority is an institution that manages the currency and monetary policy of a country or monetary union, and oversees their commercial banking system. In contrast to a commercial bank, a centra ...

intermediary An intermediary (or go-between) is a third party that offers intermediation services between two parties, which involves conveying messages between principals in a dispute, preventing direct contact and potential escalation of the issue. In la ...

that can be sent from user to user on the

peer-to-peer Peer-to-peer (P2P) computing or networking is a distributed application architecture that partitions tasks or workloads between peers. Peers are equally privileged, equipotent participants in the network. They are said to form a peer-to-peer ...

Bitcoin Gold network. The stated purpose of the hard fork is to change the

proof of work Proof of work (PoW) is a form of cryptographic proof in which one party (the ''prover'') proves to others (the ''verifiers'') that a certain amount of a specific computational effort has been expended. Verifiers can subsequently confirm this expe ...

algorithm In mathematics and computer science, an algorithm () is a finite sequence of rigorous instructions, typically used to solve a class of specific problems or to perform a computation. Algorithms are used as specifications for performing ...

so that ASICs (

Application-Specific Integrated Circuits An application-specific integrated circuit (ASIC ) is an integrated circuit (IC) chip customized for a particular use, rather than intended for general-purpose use, such as a chip designed to run in a digital voice recorder or a high-efficie ...

) which are used to mine

cannot be used to mine the Bitcoin Gold

blockchain A blockchain is a type of distributed ledger technology (DLT) that consists of growing lists of records, called ''blocks'', that are securely linked together using cryptography. Each block contains a cryptographic hash of the previous block, ...

in the hopes that enabling mining on commonly available graphics cards will democratize and decentralize the mining and distribution of the cryptocurrency. The project began as a community-driven effort with six co-founders, half of whom continue to serve on the project's Board (including Lead Developer, Hang Yin.)

History

Bitcoin Gold hard forked from the

blockchain on October 24, 2017, at block height 491407. In July 2018, Bitcoin Gold implemented a new mining algorithm. The actual algorithm that was developed by Zcash (now, Electric Coin Company) was based on parameter set <200,9>. Bitcoin Gold has modified this algorithm and is now adopting parameter set <144,5>. This new algorithm is called Equihash-BTG. The new algorithm requires more memory than the one that was originally developed by Zcash.

Network attacks

Soon after the launch, the website came under a

distributed denial of service attack In computing, a denial-of-service attack (DoS attack) is a cyber-attack in which the perpetrator seeks to make a machine or network resource unavailable to its intended users by temporarily or indefinitely disrupting services of a host conne ...

, and received criticism from

Coinbase Coinbase Global, Inc., branded Coinbase, is an American publicly traded company that operates a cryptocurrency exchange platform. Coinbase is a distributed company; all employees operate via remote work and the company lacks a physical headqua ...

and Bittrex for being hastily put together, as well as including a developer pre-mine. In May 2018, Bitcoin Gold was hit by a 51% hashing attack by an unknown actor. This type of attack makes it possible to manipulate the blockchain ledger on which transactions are recorded, and to spend the same digital coins more than once. During the attack, 388,000 BTG (worth approximately US$18 million) was stolen from several cryptocurrency exchanges. Bitcoin Gold was later delisted from Bittrex, after the team refused to help pay some of the damages. Bitcoin Gold suffered from 51% attacks again in January 2020. In July 2020 the version 0.17.2 was released as an "emergency update" in order to elude a long attack chain originated a few days before.

References

{{Bitcoin, state=expanded Cryptography Bitcoin Bitcoin clients Currency