Extension: docx
What is it? Microsoft Word 2007 document
Where’s it from? Docx is the default file format used by Microsoft Word 2007, part of the Microsoft Office 2007 productivity suite. It is based on the XML Web page standard and is compressed using the ZIP standard to save disk space.
How do I use it? Use Microsoft Office 2007; or an earlier version of Office updated with the Office Compatibility Pack for Word, Excel, and PowerPoint 2007 File Formats; or any of several free online Office 2007 docx file conversion services.
Can I safely delete or move it? Yes.
Can it be dangerous? Yes. Docx files can contain macro viruses. Use antivirus software.
–David Hakala