> For the complete documentation index, see [llms.txt](https://webauthn-doc.spomky-labs.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://webauthn-doc.spomky-labs.com/v4.0-erin-elderflower/webauthn-in-a-nutshell/ceremonies.md).

# Ceremonies

In the Webauthn context, there are two ceremonies:

* The attestation ceremony: it corresponds to the registration of a new authenticator,
* The assertion ceremony: it is used for the authentication of a user.

For both ceremonies, there are two steps to perform:

1. The creation of options: these options are sent to the authenticator and indicate what to do and how.
2. The response of the authenticator: after the user interacted with the authenticator, the authenticator computes a response that has to be verified.

Depending on the options and the capabilities of the authenticator, the user interaction may differ. It can be a simple touch on a button or a complete authentication using biometric means (PIN code, fingerprint, facial recognition…).

![The attestation ceremony](/files/-M0MHGZKakURVypatpo2)

![The assertion ceremony](/files/-M0MHB0A78pfi1meqMBn)


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