What—and who—is EOS? The new blockchain system is supposed to be a much faster and more efficient alternative to Ethereum. Ethereum was designed to be not only a cryptocurrency but also a platform for running blockchain-based computer programs called smart contracts. But it’s slow to process transactions, because every node in the Ethereum network must keep track of every account balance and the state of every smart contract. EOS’s developers say that by delegating the responsibility for processing transactions to just 21 “block producers,” which are to be elected by the community of token holders, the system will be able to achieve thousands of transactions per second (compared with just 15 per second for Ethereum). A startup called Block.one is spearheading the development of EOS’s software. Its CTO, Dan Larimer, previously created the blockchain-based financial services platform BitShares as well as Steemit, a cryptocurrency-powered publishing platform. Each relied on a novel consensus protocol called “delegated proof of stake,” which Larimer is also using with EOS. No miners: In cryptocurrencies like Bitcoin, nodes called “miners” spend lots of computing power competing for chances to add “blocks” of transactions to the chain in return for digital coins. EOS dispenses with mining in favor of allowing token holders to elect block producers, with voting power corresponding to the number of tokens an individual or organization holds. The approach should speed up transaction processing, but it has also drawn critics. Ethereum creator Vitalik Buterin has argued that it makes the system vulnerable to vote-buying that would let someone consolidate power over the network.