How OLE Works and How to get list of Methods of OLE?

Hi Experts,

I have a basic knowledge on OLE automation,

SAP Library - ABAP/4 OLE Automation Controller Through this i have done basic programs, now i need to more details on OLE <--> SAP(ABAP),

How OLE works? How to get list of methods to interact with OLE automation?

Where i can find the list of method available in SAP?

List of method means :

   CALL METHOD OF excel 'COLUMNS' = l_column

     EXPORTING

     #1 = 4. " 2 = Column B

  CALL METHOD OF excel 'WORKBOOKS' = workbook .

  CALL METHOD OF workbook 'ADD'.

etc...

Please guide me on this.