> For the complete documentation index, see [llms.txt](https://docs.agilecase.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.agilecase.com/administrator-documentation/types-of-custom-field/username.md).
# Username
### Username
The username field type allows users to "Stamp" the field, which will then display their name and can be used to ensure certain users have seen certain parts of the system.
For example, a "witness" field could be created to be stamped by a user who has been used as a witness for a transaction.
### Standard user
Standard system users can only apply their stamp to a username field; they cannot remove it once it has been placed. They will need to consult an admin if they want their stamp removed from a field.
### Admin user
Admin users are capable of both placing and removing user stamps. As an admin, clicking the small bin button will remove the current stamp, allowing you or another user to replace it.
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