Bitcoin was created in 2009 by an anonymous person, under the name of Satoshi Nakamoto. It has a maximum limit of 21 million, and 16,955,337 bitcoins are in circulation as of April 2018. It is widely accepted as the most popular cryptocurrency and has the largest market capitalization.
Ethereum is an open-source, blockchain-based platform that runs Turing-complete smart contracts. The value token of the Ethereum blockchain is called ether. It was invented by Vitalik Buterin in 2013 and later developed using a fund, US$18 million worth of bitcoins, raised via an online public crowd sale of ether in 2014.
Litecoin was released in October 2011 by Charles Lee, using a technology similar to Bitcoin. Compared to Bitcoin, the main differences are a block generation time that is decreased from 10 minutes to 2.5 minutes per block; a maximum limit of 84 million for Litecoin, which is four times as high as that of Bitcoin; and the adoption of a different hashing algorithm.
Dash (formerly known as XCoin and Darkcoin) was initially proposed in January 2014 by Evan Duffield, who is also the lead developer. Dash has released the decentralized governance by blockchain system, and it is the first decentralized autonomous organization. It is a privacy-centric cryptocurrency. It uses a coin-mixing service called PrivateSend to anonymize transactions and InstantSend to allow for instant transactions.
The two creators of Dogecoin, Billy Markus and Jackson Palmer, hoped to create a fun cryptocurrency that would appeal to more people. Hence, they used the Shiba Inu dog from the “Doge” Internet meme as the logo and created Dogecoin in 2013. There is no limit to the number of Dogecoins to be produced. Transactions of Dogecoins are made in online communities such as Reddit and Twitter.
Monero (originally named BitMonero) is another open-source, privacy-centric altcoin created in 2014. It is a 100% PoW cryptocurrency. The privacy of transactions is protected by ring signatures (that hide the sending address), RingCT (that hides the amount of transactions), and stealth addresses (that hide the receiving address).
BitShares is an open-source public cryptocurrency platform that offers a variety of features and was invented by Daniel Larimer. It allows users to issue and trade stocks or debts on the distributed ledger.
MaidSafeCoin is designed for the secure-access-for-everyone network. The data of users and transactions are safe and secure. The network encourages users to provide their resources, such as storage space, central processing unit power, and bandwidth, by giving them the coins as a digital token. The maximum number of MaidSafeCoins in circulation is 4.3 billion.
Nxt was released in 2013 by an anonymous software developer, BCNext. It is the first cryptocoin that uses purely PoS for consensus, thus making the money supply static—1 billion in the case of Nxt. The block generation rate is 1 minute per block. Despite the additional risks, the complex core infrastructure of Nxt makes it a flexible platform because it is easier to build external services on top. For example, it allows for currency creation and has a messaging system and marketplace.
Bytecoin is the first cryptocurrency invented with the CryptoNote protocol. It secures transactions because the identities of the sender and the receiver and the amount of transaction are all concealed. The number of Bytecoins is capped at 184.47 billion, and the block generation time is 120 seconds per block.
In addition to the aforementioned 10 cryptocurrencies, the following altcoins have also been drawing investor attention.
Ethereum Classic (ETC). Ethereum Classic is a continuation of Ethereum’s original blockchain, so it is also an open-source, blockchain-based platform that supports Turing-complete smart contract. It was created after the hard-fork debate in 2016 and is designed to allow smart contracts to run exactly as programmed without any possibility of third-party interference.
Factom (FCT). Launched in 2014, Factom is an open-source, distributed, and decentralized protocol built on top of Bitcoin. Instead of storing only financial transactions, Factom blockchain technology can record any type of data, making it an ideal platform for real-world business record-keeping systems.
NEM (XEM). NEM is a P2P platform that provides services like payment and messaging system. It uses a proof of importance algorithm, so it does not require much computing power and energy to mine. Together with Mijin, which is a licensed version of NEM, it is the first public/private blockchain combination.
Ripple (XRP). Ripple was created by Chris Larsen and Jed McCaleb. It is one of the first cryptocurrencies not developed based on Bitcoin’s protocol. It is an open-source, distributed P2P payment network, but it is centralized—managed by the company. Any currencies, including the ripple digital currency and ad hoc currencies that have been created by users, can be transferred on the payment system. The maximum number of ripple is 100 billion.
Zcash (ZEC). Launched in 2016, Zcash provides privacy and selective transparency of transactions. Although the transactions are recorded in the public blockchain, Zcash allows for completely transparent transactions using t-addresses, and it can also offer a greater level of privacy to its users using z-addresses. It adopts zero-knowledge cryptography to protect the sender, amount, and recipient of a transaction using a z-address. As with bitcoin, the total amount of Zcash is capped at 21 million