The Input Fields command and Field Definition command, both available on the Tools menu, display useful information on fields and programs. The Input Fields command lists the controls on the loaded form (program). The Field Definition command shows full details for whatever control has the focus. User Settings can be used to withdraw access to these options.
The F8 key can also be used to access the field definition for whatever field has the focus. The Security Target is used for field level security; if it is blank, field level security can not be applied.