# semaphore

> semaphore: Anonymous signalling protocol. Technology: zero-knowledge proofs.

Part of the Soda Labs Privacy Hub, a neutral directory of the on-chain privacy
landscape: https://www.sodalabs.xyz/privacy-hub

## Key facts

- Entry type: Privacy project
- Category: Anonymous signalling protocol
- Technology: Zero-knowledge proofs (ZK)
- Website: https://semaphore.pse.dev
- Tags: ZK, groups, voting
- Canonical page: https://www.sodalabs.xyz/privacy-hub/semaphore

## Overview

Semaphore is the primitive a large part of this field is built on: prove you belong to a group and broadcast a signal, exactly once, without revealing which member you are. It is small, audited, well documented and reused everywhere from anonymous voting to whistleblowing tools, which is the highest compliment a cryptographic library can receive. It is a building block from Privacy and Scaling Explorations rather than an application, so what it protects depends on how it is used.

## About Zero-knowledge proofs

One party proves a statement about hidden data is true without revealing the data the statement is about. Compared side by side with the other approaches at https://www.sodalabs.xyz/taxonomy.

## Sources

- [Website](https://semaphore.pse.dev)
- [Docs](https://docs.semaphore.pse.dev)
- [Whitepaper](https://semaphore.pse.dev/whitepaper-v1.pdf)
- [Source](https://github.com/semaphore-protocol)
- [Explorer](https://explorer.semaphore.pse.dev/)

## Related entries

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- [Hinkal](https://www.sodalabs.xyz/privacy-hub/hinkal): Private DeFi layer
- [Miden](https://www.sodalabs.xyz/privacy-hub/miden): Client-side proving chain (upcoming)
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