If I copy data from Excel, how can I get full access to it.
From what I see, there is a format called "BIFF8".
Is this documented? How does it differ from the xls file format?
BIFF format is a Microsoft document, not less than: MICROSOFT OFFICE EXCEL 97-2007 BINARY FILE FORMAT SPECIFICATION .
BIFF is a file format used by older versions of Excel..xlsx is an XML-based format.