Polyhedra Network (ZKJ) is a decentralized finance (DeFi) platform built on the Ethereum blockchain that focuses on providing privacy and security for users. It utilizes zero-knowledge proofs to ensure anonymity in transactions and smart contracts. Users can participate in various DeFi activities such as lending, borrowing, and trading assets while maintaining their privacy. Polyhedra Network aims to create a secure and efficient ecosystem for DeFi participants to interact and transact without compromising their personal information.