Free text is the ability to manually enter certain details on a purchase order. This ability is controlled by the data entry permissions in the user and role permissions. These permissions can be given for vendors, delivery locations, charge to accounts, items, and department.
In most cases users should be restricted from free text for fields other than Items. If a user is allowed free text then the field will not be fully managed and controlled in the system. This can also cause problems when trying to link to a financial package.