# Ceremonies

In the Webauthn context, there are two ceremonies:

* The attestation ceremony
* 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…).

## Attestation ceremony

This ceremony aims at registering an authenticator. It can be used during the creation of a new user account or when an existing user wants to add an additional authenticator.

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

## Assertion ceremony

This ceremony aims at authenticating a user. The user will be asked to interact with one of its authenticators. Additional authentication means, such as PIN code or fingerprint, may be required.

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


---

# 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://webauthn-doc.spomky-labs.com/v4.5/webauthn-in-a-nutshell/ceremonies.md?ask=<question>
```

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.