Overview
MetaMask is a free, non-custodial cryptocurrency wallet available as a browser extension and mobile app. It allows users to store, send, and receive Ethereum-based assets and interact with decentralized applications (dApps). MetaMask became the most widely used gateway to Web3, managing private keys locally on the user's device.
How It Works
MetaMask generates and stores a user's private keys locally, protected by a password and backed up by a seed phrase. When a user interacts with a dapp, MetaMask signs transactions in the browser or app and broadcasts them to the network. It supports multiple networks, token standards, and a swap feature that routes trades through aggregators.
Why It Matters
MetaMask is the default onboarding tool for Ethereum and EVM chains, and its browser extension defined how millions of users experience Web3. Its self-custody model, combined with its popularity, makes it both a security benchmark and a target for phishing and social engineering. Its recent platform monetization and expansion into smart accounts reflect the pressure on wallets to evolve beyond basic key storage.
Related Concepts
MetaMask is a non-custodial Wallet that manages Private Keys and Seed Phrases. It supports dapp interactions and is an entry point to concepts like Account Abstraction and ENS-based identity.