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# Curve25519

An elliptic curve that enables X25519 key agreement and Ed25519 signatures.

```
enum Curve25519
```

## Topics

### Performing operations

[`Curve25519.KeyAgreement`](/documentation/CryptoKit/Curve25519/KeyAgreement)

A mechanism used to create a shared secret between two users by
performing X25519 key agreement.

[`Curve25519.Signing`](/documentation/CryptoKit/Curve25519/Signing)

A mechanism used to create or verify a cryptographic signature using
Ed25519.


---

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