XLS

File Format
Name	XLS
Ontology	Electronic File Formats Document XLS
Extension(s)	.xls
MIME Type(s)	application/vnd.ms-excel

Microsoft Office EXCEL 97-2007

The Excel Binary File Format (.xls) Structure is the binary file format used by Microsoft Excel 97, 2000, 2002, and Office Excel 2003. It is also supported by Microsoft Office Excel 2007.

References

• Binary file format specification *.xls (97-2007) format
• Why are the Microsoft Office file formats so complicated? (And some workarounds)