Notebook is an identity infrastructure layer that allows existing identity providers to interact with Web3 while maintaining anonymity and privacy using zero-knowledge proofs. It can be used to increase the safety of DeFi, governance, and airdrops. Notebook enables creators and communities to run Sybil-resistant airdrops, DAOs to verify the humanity and aggregate the credentials of participants, and lending protocols to build credit scoring systems for offering lower-collateralized loans.