# UserEmail Users can have multiple UserEmail registered on the platform. They have the following properties: | Property | Type | description | | -------------- | -------------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------- | | hash | ID | Hashed user email. Always use the same hashing function (ex: `SHA-256`) in your datamart and all its integrations to allow proper matching between data flows. | | email | String | *Optional*. User's email, not hashed. | | creation\_ts | Timestamp | When the email was registered on the platform | | expiration\_ts | Timestamp (optional) | Email's eventual expiration timestamp | The `hash` property is mandatory and is the property used to identify a user (provided in `$hash` property in User activities request). --- # 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://developer.mediarithmics.io/user-points/user-identifiers/useremail.md?ask= ``` 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.