Passkeys introduce a passwordless authentication model built on asymmetric cryptography and open standards such as WebAuthn and FIDO2. In this talk, we will explore the technical mechanics of passkeys: from key pair generation and registration with the relying party, to the authentication flow via challenge-response. We will examine how passkeys mitigate common attacks such as phishing, credential stuffing, and database breaches, and discuss the implications for backend architectures, identity management, and user experience. The goal is to provide a clear understanding of the underlying mechanisms and best practices for adoption.