A null-terminated string that contains the application name that Windows uses. If this argument is not supplied or is NULL, CWinApp uses the resource string AFX_IDS_APP_TITLE or the filename of the executable file.
You should construct one global object of your CWinApp-derived class. You can have only one CWinApp object in your application. The constructor stores a pointer to the CWinApp object so that WinMain can call the object's member functions to initialize and run the application.