User-Defined Fields 
Use
SAP Business One enables you to add user-defined fields that might be essential for your business’s day-to-day activities.
You can display user-defined fields in the print layout designer or in the Query Generator window.
To display the Manage User Fields window, choose Tools ® User-Defined Fields ® Manage User Fields.
For more information on user-defined fields, see http://help.sap.com
See also: