Ethereum Name Service (ENS) is a distributed, open, and extensible naming system based on the Ethereum blockchain. ENS converts human-readable Ethereum addresses like john.eth into the machine-readable alphanumeric codes you know from wallets like Metamask. The reverse conversion -- associating metadata and machine-readable addresses with human-readable Ethereum addresses -- is also possible.

The goal of Ethereum Name Service is to make the Ethereum-based web easier to access and comprehend for humans - similar to how the Internet’s Domain Name Service makes the internet more accessible. Like DNS, ENS also uses a system of dot-separated hierarchical names called domains with domain owners fully controlling their subdomains.