Self is a company that provides digital identity infrastructure for both Web2 and Web3 environments. It uses zero-knowledge cryptography so that users can prove aspects of their identity without revealing sensitive information to the verifier or storing it in an external database. Self supports selective disclosure of attributes (for example age or nationality) and works to verify that users are real humans rather than bots. The technology is designed to integrate with on-chain and off-chain systems, enabling applications such as age verification, wallet recovery, bot-protection, and Sybil-resistant polling.