# How Biometric Proof-of-Humanity Works

Humanity is building out a global infrastructure for **human-based** [**Self-Sovereign Identities (SSI)**](https://en.wikipedia.org/wiki/Self-sovereign_identity), referring to decentralized identity models that provide users with full control and autonomy of their own identity data.

To ensure **Proof-of-Humanity (PoH)**, Humanity uses two methods:

1. **Enrollment App**: Available on both Android and iOS, it allows users to scan their palm print capturing the surface patterns of the palm to receive a palm print [Verifiable Credential](https://en.wikipedia.org/wiki/Verifiable_credentials) (VC) using a [CNN](https://www.ibm.com/topics/convolutional-neural-networks) machine learning model.
2. **Humanity Scanners:** Hardware devices that use infrared light to map the unique vein patterns beneath the skin. These vein patterns are only detectable in a living body, making them impossible to replicate and one of the most secure identification methods available.

The **mobile app provides a basic yet robust Proof-Of-Humanity within Humanity** while the activation through the **Humanity Scanners provide a full enrollment.**

**In both cases Humanity keeps personal data entirely confidential due to the implementation of** [**Zero-Knowledge (ZK) Proofs**](https://en.wikipedia.org/wiki/Zero-knowledge_proof)**.**

<figure><img src="/files/zBmpB6VDTgJnZ502D2ua" alt=""><figcaption></figcaption></figure>


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