Microsoft File Formats
Microsoft Office File Formats documentation provides comprehensive technical specifications for the.doc,.ppt.xls, and.xlsb file formats as produced by the next Microsoft Office applications:
.doc: Microsoft Office Word
.ppt: Microsoft Office Power-point
.xls: Microsoft Office Excel
.xlsb: Microsoft Office Excel
.XPS: Microsoft XPS Format
Additionally, Microsoft provides comprehensive technical specifications for other file formats implemented in specific Microsoft Office applications, for example, Outlook Personal Folders (.pst) file format.