Which type of role is assigned to each user, allowing only one per person?

The type of role assigned to each user, allowing only one per person, is the User Role. User Roles determine the permissions and access level within the Marketing Cloud, influencing what actions a user can perform and what data they can access. By providing a unique User Role to each individual, the system ensures that access is tailored to the specific needs and responsibilities of that person within the organization, enhancing security and operational efficiency.

Other roles, such as Workspace Role and Admin Role, are typically designed to be assigned based on project or organizational needs and may not restrict assignment to just one per person in the same way that a User Role does. Guest Roles are generally meant for external access with limited permissions and do not replace the primary User Role structure.