# Biometrics {% hint style="info" %} **Biometrics** are unique physical or behavioral characteristics used to identify individuals. These can include fingerprints, facial recognition, iris scans, voice patterns, or other uniquely identifying behavior. Biometrics are are difficult to replicate and inherently tied to the individual, making them useful for digital authentication. {% endhint %} ## Traditionally, biometrics have been integrated into centralized systems controlled by institutions like governments, banks, or tech companies (e.g., Apple’s Face ID). While this adds convenience, it raises significant privacy and security concerns: **Who controls this sensitive data?** **How is it stored?** **Could it be stolen or misused?** Centralized control over biometrics can lead to data breaches, surveillance, or the abuse of personal information. *** ## **Biometrics in a Decentralized System** **Human Keys** take biometrics to the next level by embedding them into a decentralized framework, where the individual retains complete control over their biometric data. With Human Keys, biometrics become the basis for self-sovereign identities—no centralized authority holds your data. Instead, your biometric data is used to create cryptographic keys that are under your sole control. In this model, biometrics aren't stored or shared with any third party. Instead, they are locally used to generate Human Keys that can be used for authentication across decentralized applications, without ever needing to expose or store the biometric data. This offers a privacy-first approach, combining the strength of biometrics with the security and control of decentralized cryptography. *** ## **Privacy-Preserving Biometrics** By integrating **zero-knowledge proofs**, **Human Keys** allow users to prove aspects of their identity using biometrics—such as confirming they are a unique human—without revealing any personal details. This privacy-preserving mechanism ensures that while biometrics authenticate identity, no actual biometric data is shared or exposed in the process. The result is a system where individuals can confidently use their biometrics without fear of surveillance, theft, or misuse. *** ## **The Future of Biometrics with Human Keys** Biometrics, when combined with decentralized identity frameworks like Human Keys, represent a shift towards more secure and private forms of identity verification. By decentralizing control and protecting biometric data through cryptography, we unlock the true potential of biometrics—offering both security and privacy in the digital world. As digital interactions evolve, biometrics will be at the forefront of secure, self-sovereign identity, allowing individuals to seamlessly and safely navigate the web without sacrificing control over their personal information. --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://developer.holonym.id/concepts/human-keys/biometrics.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.