Bitcoin is a worldwide cryptocurrency and digital payment system called the first decentralized digital currency, since the system works without a central repository or single administrator. It was invented by an unknown programmer, or a group of programmers, under the name Satoshi Nakamoto and released as open-source software in 2009. The system is peer-to-peer, and transactions take place between users directly, without an intermediary. These transactions are verified by network nodes and recorded in a public distributed ledger called a blockchain. As of February 2015, over 100,000 merchants and vendors accepted bitcoin as payment.
Ethereum is an open-source, public, blockchain-based distributed computing platform featuring smart contract functionality. It provides a decentralized Turing-complete virtual machine, the Ethereum Virtual Machine (EVM), which can execute scripts using an international network of public nodes. Ethereum also provides a cryptocurrency token called "ether", which can be transferred between accounts and used to compensate participant nodes for computations performed. "Gas", an internal transaction pricing mechanism, is used to mitigate spam and allocate resources on the network. Ethereum was proposed in late 2013 by Vitalik Buterin, a cryptocurrency researcher and programmer. Development was funded by an online crowdsale during July–August 2014. The system went live on 30 July 2015. In 2016 Ethereum was forked into two blockchains, as a result of the collapse of The DAO project, thereby creating Ethereum Classic.
Litecoin is a peer-to-peer cryptocurrency and open source software project released under the MIT/X11 license. Creation and transfer of coins is based on an open source cryptographic protocol and is not managed by any central authority. While inspired by, and in most regards technically nearly identical to Bitcoin (BTC), Litecoin has some technical improvements over Bitcoin, and most other major cryptocurrencies, such as the adoption of Segregated Witness, and the Lightning Network. These effectively allow a greater number of transactions to be processed by the network in a given time, reducing potential bottlenecks, as seen with Bitcoin. Litecoin also has almost zero payment cost and facilitates payments approximately four times faster than Bitcoin.
Monero (XMR) is an open-source cryptocurrency created in April 2014 that focuses on privacy, decentralisation and scalability. Unlike many cryptocurrencies that are derivatives of Bitcoin, Monero is based on the CryptoNote protocol and possesses significant algorithmic differences relating to blockchain obfuscation. Monero experienced rapid growth in market capitalization (from US$5M to US$185M) and transaction volume during the year 2016, partly due to adoption in 2016 by major darknet market AlphaBay.
Zcash is a cryptocurrency that offers privacy and selective transparency of transactions. Zcash payments are published on a public blockchain, but the sender, recipient, and amount of a transaction may remain private. The Zcash trade symbol, ZEC, is not an official ISO 4217. Like Bitcoin, Zcash has a fixed total supply of 21 million units. In April 2017, Zcash was included among the cryptocurrencies that can be managed by Jaxx, a wallet platform available for Android and iOS. On April 4th 2017, Zcash entered the top 10 cryptocurrencies by market cap.
Ethereum Classic (ETC)
Ethereum Classic is an open-source, public, blockchain-based distributed computing platform featuring smart contract (scripting) functionality. It provides a decentralized Turing-complete virtual machine, the Ethereum Virtual Machine (EVM), which can execute scripts using an international network of public nodes. Ethereum Classic also provides a value token called "classic ether", which can be transferred between participants and is used to compensate participant nodes for computations performed. The classic ether token is traded on cryptocurrency exchanges under the ticker symbol ETC. Gas, an internal transaction pricing mechanism, is used to prevent spam on the network and allocate resources proportionally to the incentive offered by the request.
NEM is a peer-to-peer cryptocurrency and blockchain platform launched on March 31, 2015. Written in Java, with a C++ version in the works, NEM has a stated goal of a wide distribution model and has introduced new features to blockchain technology such as its proof-of-importance (POI) algorithm, multisignature accounts, encrypted messaging, and an Eigentrust++ reputation system. The NEM blockchain software is used in a commercial blockchain called Mijin, which is being tested by financial institutions and private companies in Japan and internationally.
Dash (formerly known as Darkcoin and XCoin) is an open source peer-to-peer cryptocurrency that offers all the same features as Bitcoin but also has advanced capabilities, including instant transactions (InstantSend), private transactions (PrivateSend) and decentralized governance (DGBB). Dash's decentralized governance and budgeting system makes it the first decentralized autonomous organization. Dash uses a two-tier architecture to power its network. The first tier consists of miners who secure the network and write transactions to the blockchain. The second tier consists of masternodes which enable the advanced features of Dash.
Dogecoin is a cryptocurrency featuring a likeness of the Shiba Inu dog from the "Doge" Internet meme as its logo. Introduced as a "joke currency" on 8 December 2013, Dogecoin quickly developed its own online community and reached a capitalization of US$60 million in January 2014. As of June 2017, it has a capitalization of US$340 million. Compared with other cryptocurrencies, Dogecoin has a fast initial coin production schedule: 100 billion coins have been in circulation by mid 2015 with an additional 5.256 billion coins every year thereafter. As of 30 June 2015, the 100 billionth Dogecoin has been mined.
Namecoin is a cryptocurrency and the first fork of the bitcoin software. It is based on the code of bitcoin and uses the same proof-of-work algorithm. It is limited to 21 million coins. Unlike bitcoin, Namecoin can store data within its own blockchain transaction database. The original proposal for Namecoin called for Namecoin to insert data into bitcoin's blockchain directly. Anticipating scaling difficulties with this approach, a shared proof-of-work (POW) system was proposed to secure new cryptocurrencies with different use cases.