You can customize the generated Word specification document with the options in the Publish → Generate Word Specification dialog. If you have Word 2000, Word XP, or Word 2003 installed, the Axure RP installer will install the Microsoft Office Compatibility Pack, which enables these versions of Word to open, edit, and save. docx files, such as LibreOffice - to view the generated Word file and to edit the Word template file (more on that later). You don't need Word installed on your computer in order to generate the Word documentation, but you will need Word or Word for Mac - or another tool that can open. The specification file generated from RP is in Microsoft Word's. To generate a Word specification document for your prototype, go to Publish → Generate Word Specification.
This output type is one option available to you when your project requires a formal print deliverable. The Word specification is an automatically generated Microsoft Word document that serves as the functional specification component of your Axure RP file if needed.