ethereum

Ethereum is a decentralized, open-source blockchain platform for programmable smart contracts and decentralized applications. Proposed in 2013–2014 by Vitalik Buterin and developed by the Ethereum Foundation and a global community, the project launched its mainnet in 2015.

Technologically, Ethereum maintains a global state on a distributed ledger and enables code execution via the Ethereum Virtual Machine (EVM). The network's native cryptocurrency, Ether (ETH), is used to pay for computation and transactions through a unit called gas.

Smart contracts are self-executing programs that run on the EVM, enabling decentralized applications (dApps) across finance, gaming, supply chains, and more. Tokens following common standards, such as ERC-20 for fungible tokens and ERC-721 for non-fungible tokens, are widely used within the ecosystem.

In governance and consensus terms, Ethereum transitioned from proof-of-work to proof-of-stake with The Merge in 2022, integrating the original execution layer with a new consensus layer (the Beacon Chain). The upgrade reduced energy use and set the stage for scalability improvements, including future shard chains and Layer 2 rollups that process transactions off the main chain.

The Ethereum ecosystem is maintained by a global community of developers, researchers, and organizations. Development is coordinated through Ethereum Improvement Proposals (EIPs) and is supported by the Ethereum Foundation and various foundations, labs, and companies.

As a leading platform for decentralized finance (DeFi), non-fungible tokens (NFTs), and complex dApps, Ethereum has a large, active ecosystem. It faces challenges such as network congestion, high and variable gas fees, security risks in smart contracts, and evolving regulatory considerations.