by
Tayyab Arif , IT Network Engineer , Huawei Technologies
Xlsx:
This is the XML-based default file format for Excel 2007 / 10. This file format cannot store Ms Visual Basic for Applications (VBA) macrocode or Ms Office Excel version 4.0 macro sheets (.xlm).
Xlsm:
This is the file format based on XML and macro-enabled for Excel 2007 / 10. This file format Stores VBA macrocode or Excel version 4.0 macro sheets (.xlm).
Xls:
This file format is used in earlier version of Excel 97 – 2003 and known as Binary file format (BIFF8).