what's Urbit?

Urbit is a decentralized operating system and network designed to provide users with sovereign control over their digital lives through personal servers. It operates as a clean-slate platform, separating the OS (Arvo), programming language (Hoon), and virtual machine (Nock) to enable peer-to-peer communication without reliance on centralized cloud services. Urbit IDs, structured as a hierarchical namespace (galaxies, stars, planets, moons), function as unique digital identities and are implemented as ERC-721 NFTs on the Ethereum blockchain, allowing users to own and trade their "addresses" in a scarcity-based system. The platform emphasizes privacy and permanence, with users running their own instances to host apps, data, and communications. Nock serves as the core interpreter, a minimal functional language that ensures deterministic computation, while Hoon provides a higher-level interface for development. Urbit's network uses Ames for secure messaging and Vere for runtime execution, fostering a federated ecosystem where users can build and share applications without intermediaries. Though not a traditional blockchain, Urbit integrates crypto primitives for identity and has inspired crypto projects like Nockchain, leveraging its computational model for verifiable systems. It aims to replace fragmented web services with a unified, user-owned computing environment.

Urbit deployed production Directed Messaging, its Named Data Networking implementation.