The Z-OptimiZr Native XML file optimization feature enables to significantly reduce the size of all Microsoft Office XML files like DOCX, PPTX, XLSX etc. The average volume reduction ratios obtained on XML files are generally around 50%.

 
"Native" means that the optimized Microsoft Office XML files remain fully standard Microsoft Office XML files.
For instance an optimized DOCX file remains a fully standard DOCX file, an optimized PPTX file remains a fully standard PPTX file etc.
Thus, these optimized Microsoft Office files can be opened directly in Microsoft Office as well as in any application able to open Microsoft Office files. There is no need for any 'decompression' of the optimized files.
 

This is the list of Microsoft Office XML (and Open Office) files that can be natively optimized by the Native XML Optimization feature:

•Microsoft Word files:
DOCX, DOCM, DOTX, DOTM

•Microsoft PowerPoint files:
PPTX, PPSX, PPTM, POTX, POTM, PPAM, PPSM, SLDX, SLDM, THMX

•Microsoft Excel files:
XLSX, XLSM, XLTX, XLTM, XLSB, XLAM

•Microsoft Visio Files:
VSDX, VSSX, VSTX, VDSM, VSSM, VSTM

•Open Office Files:
ODT, ODS, ODP

The Z-OptimiZr Native XML Optimization for MS Office Files feature does not require Microsoft Office installed on the computer.
This feature has no dependencies towards Microsoft Office.