MetaMask is a digital wallet and browser extension designed for managing Ethereum and other ERC-20 tokens. Launched in 2016 by ConsenSys, it allows users to securely store, send, and receive cryptocurrency, as well as connect to decentralized applications directly from their browser. MetaMask plays a key role in the Web3 ecosystem, serving as a gateway for users to engage with blockchain-based services and decentralized finance platforms.