In this documentation we sometimes refer to the "Codes Table": it provides a list of IDs that are needed in several API calls:
- List IDs and GUIDs
- Group IDs
- Data field codes
Data fields, also called personal data fields, are defined in your MailUp admin console under Manage > Personal Data Fields.
By default, you can define up to 11 custom fields. You can grow this number to 40 customizable custom fields by adding the Marketing+ feature package to your account.
The Codes Table can be accessed in your MailUp admin console by navigating to Settings > Codes Table
Here is an example on the section that describes the personal data fields.
What's a "campo"?
The field code uses the word "CAMPO" because MailUp's original source code was developed in Italy. "Campo" means "Field" in Italian ![(smile)](/wiki/s/773435051/6452/7f2c16da68ca06592d255ebcc4f74e865928ceee/_/images/icons/emoticons/smile.png)
![(smile)](/wiki/s/773435051/6452/7f2c16da68ca06592d255ebcc4f74e865928ceee/_/images/icons/emoticons/smile.png)