.DOCX

Office Open XML Document

Introduction

DOCX is the default format of Microsoft Word since Word 2007, replacing the older binary .doc. It is part of Office Open XML, standardised as ECMA-376 and ISO/IEC 29500. A DOCX file is a ZIP archive of XML files: the text and its formatting, the styles, the numbering of lists, comments, headers, footers and the pictures.

Related extensions use the same layout: .docm for documents with macros and .dotx for templates.

Software

Structure

The ZIP package follows the Open Packaging Conventions. [Content_Types].xml gives the type of each part, and _rels/.rels points to the main document, word/document.xml. Its body is a list of paragraphs (w:p), each made of runs (w:r) of text (w:t) that share the same formatting. Tables, section settings and references to pictures sit among the paragraphs.

  1. zip[Content_Types].xml the media type of each partXML
  2. zip_rels/.rels points to the main document and propertiesXML
  3. zipword/document.xml the body: paragraphs, runs, tablesXML
  4. zipword/styles.xml, numbering.xml, settings.xmlXML
  5. zipword/media/ the picturesimages
  6. zipdocProps/ title, author, dates and statisticsXML
The main parts inside a DOCX package.