ActiveX DLLs in VB

when we should make use of Activex Dlls?In ActiveX DLLs what is the equivalent of END command?

[Lothar Haensler]

there is no equivalent of an END command in an ActiveX Dll. The DLL is unloaded automatically as soon as the last instance of the client programs that use that DLL is unloaded.

when to use? very broad subject: I'd say whenever there is a chance that the logic in that dll is going to be used by another app.