Ethereum is a decentralized blockchain platform and cryptocurrency that was created by Vitalik Buterin and launched in 2015. It is the second-largest cryptocurrency by market capitalization, after Bitcoin. Ethereum is unique in that it allows developers to build and deploy smart contracts and decentralized applications (DApps) on its blockchain.
Smart contracts are self-executing contracts with the terms of the agreement directly written into code. They automatically execute when certain conditions are met, without the need for intermediaries or central authorities. This enables a wide range of applications, from decentralized finance (DeFi) and non-fungible tokens (NFTs) to supply chain management and decentralized governance systems.
Ethereum's native cryptocurrency is called Ether (ETH), which is used to pay for transaction fees and computational services on the network. Ether can also be traded on various cryptocurrency exchanges like other digital currencies.
Ethereum's blockchain operates on a proof-of-work (PoW) consensus mechanism, similar to Bitcoin, which requires miners to solve complex mathematical problems to validate and add transactions to the blockchain. However, Ethereum has been working on transitioning to a proof-of-stake (PoS) mechanism, known as Ethereum 2.0, which aims to improve scalability, energy efficiency, and security.