...and if you open a Microsoft Word .docx file in BBEdit or a similar editor you will find lots of XML tags that can easily be edited in a text editor like BBEdit that doesn't attempt to interpret the tags. Docx is a Microsoft variant of the ODF (Open Document For Office Applications) that was developed by Sun Microsystems for their Open Office product and later released into Open Source. Microsoft's modifications to ODF were primarily intended to make docx incompatible with ODF and create a closed standard controlled by Microsoft.

The following are examples of the same the same document in ODF and DOCX formats:

NOTE:
  • The difference in the two examples is exaggerated because internally docx and odf (and Pages as well) files are actually packages and the necessary formatting information is organized differently into multiple folders and files in each.
  • I highlighted the actual content in RED.


Originally Posted by ODF
<?xml version="1.0" encoding="UTF-8"?>
<office:document-content xmlns:office="urn:oasis:names:tc:opendocument:xmlns:office:1.0" xmlns:style="urn:oasis:names:tc:opendocument:xmlns:style:1.0" xmlns:text="urn:oasis:names:tc:opendocument:xmlns:text:1.0" xmlns:table="urn:oasis:names:tc:opendocument:xmlns:table:1.0" xmlns:draw="urn:oasis:names:tc:opendocument:xmlns:drawing:1.0" xmlns:fo="urn:oasis:names:tc:opendocument:xmlns:xsl-fo-compatible:1.0" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:meta="urn:oasis:names:tc:opendocument:xmlns:meta:1.0" xmlns:number="urn:oasis:names:tc:opendocument:xmlns:datastyle:1.0" xmlns:svg="urn:oasis:names:tc:opendocument:xmlns:svg-compatible:1.0" xmlns:chart="urn:oasis:names:tc:opendocument:xmlns:chart:1.0" xmlns:dr3d="urn:oasis:names:tc:opendocument:xmlns:dr3d:1.0" xmlns:math="http://www.w3.org/1998/Math/MathML" xmlns:form="urn:oasis:names:tc:opendocument:xmlns:form:1.0" xmlns:script="urn:oasis:names:tc:opendocument:xmlns:script:1.0" xmlns:ooo="http://openoffice.org/2004/office" xmlns:ooow="http://openoffice.org/2004/writer" xmlns:oooc="http://openoffice.org/2004/calc" xmlns:dom="http://www.w3.org/2001/xml-events" xmlns:xforms="http://www.w3.org/2002/xforms" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:rpt="http://openoffice.org/2005/report" xmlns:of="urn:oasis:names:tc:opendocument:xmlns:of:1.2" xmlns:xhtml="http://www.w3.org/1999/xhtml" xmlns:grddl="http://www.w3.org/2003/g/data-view#" xmlns:officeooo="http://openoffice.org/2009/office" xmlns:tableooo="http://openoffice.org/2009/table" xmlns:drawooo="http://openoffice.org/2010/draw" xmlns:calcext="urn:org:documentfoundation:names:experimental:calc:xmlns:calcext:1.0" xmlns:loext="urn:org:documentfoundation:names:experimental:office:xmlns:loext:1.0" xmlns:field="urn:openoffice:names:experimental:ooo-ms-interop:xmlns:field:1.0" xmlns:formx="urn:openoffice:names:experimental:ooxml-odf-interop:xmlns:form:1.0" xmlns:css3t="http://www.w3.org/TR/css3-text/" office:version="1.2"><office:scripts/><office:font-face-decls><style:font-face style:name="Tahoma1" svg:font-family="Tahoma"/><style:font-face style:name="Times New Roman" svg:font-family="'Times New Roman'" style:font-family-generic="roman" style:font-pitch="variable"/><style:font-face style:name="Arial" svg:font-family="Arial" style:font-family-generic="swiss" style:font-pitch="variable"/><style:font-face style:name="Lucida Bright Regular" svg:font-family="'Lucida Bright Regular'" style:font-family-generic="swiss" style:font-pitch="variable"/><style:font-face style:name="Arial1" svg:font-family="Arial" style:font-family-generic="system" style:font-pitch="variable"/><style:font-face style:name="Tahoma" svg:font-family="Tahoma" style:font-family-generic="system" style:font-pitch="variable"/></office:font-face-decls><office:automatic-styles><style:style style:name="P1" style:family="paragraph" style:parent-style-name="Standard"><style:paragraph-properties fo:margin-left="0pt" fo:margin-right="0pt" fo:text-indent="24.01pt" style:auto-text-indent="false"/><style:text-properties style:font-name="Lucida Bright Regular" fo:font-size="10.5pt" officeooo:rsid="001aa88f" officeooo:paragraph-rsid="001aa88f" style:font-size-asian="9.14999961853027pt" style:font-size-complex="10.5pt"/></style:style></office:automatic-styles><office:body><office:text><text:sequence-decls><text:sequence-decl text:display-outline-level="0" text:name="Illustration"/><text:sequence-decl text:display-outline-level="0" text:name="Table"/><text:sequence-decl text:display-outline-level="0" text:name="Text"/><text:sequence-decl text:display-outline-level="0" text:name="Drawing"/></text:sequence-decls><text:p text:style-name="P1">Now is the time for all good men to come to the aid of their country</text:p></office:text></office:body></office:document-content>>

Originally Posted by docx
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<w:document xmlns:o="urn:schemas-microsoft-com:office:office" xmlns:r="http://schemas.openxmlformats.org/officeDocument/2006/relationships" xmlns:v="urn:schemas-microsoft-com:vml" xmlns:w="http://schemas.openxmlformats.org/wordprocessingml/2006/main" xmlns:w10="urn:schemas-microsoft-com:office:word" xmlns:wp="http://schemas.openxmlformats.org/drawingml/2006/wordprocessingDrawing" xmlns:wps="http://schemas.microsoft.com/office/word/2010/wordprocessingShape" xmlns:wpg="http://schemas.microsoft.com/office/word/2010/wordprocessingGroup" xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" xmlns:wp14="http://schemas.microsoft.com/office/word/2010/wordprocessingDrawing" xmlns:w14="http://schemas.microsoft.com/office/word/2010/wordml" mc:Ignorable="w14 wp14"><w:body><w:p><w:pPr><w:pStyle w:val="Normal"/><w:ind w:left="0" w:right="0" w:firstLine="480"/><w:rPr><w:rFonts w:ascii="Lucida Bright Regular" w:hAnsi="Lucida Bright Regular"/><w:sz w:val="21"/><w:szCs w:val="21"/></w:rPr></w:pPr><w:r><w:rPr><w:rFonts w:ascii="Lucida Bright Regular" w:hAnsi="Lucida Bright Regular"/><w:sz w:val="21"/><w:szCs w:val="21"/></w:rPr><w:t>Now is the time for all good men to come to the aid of their country</w:t></w:r></w:p><w:sectPr><w:type w:val="nextPage"/><w:pgSz w:w="12240" w:h="15840"/><w:pgMar w:left="1134" w:right="1134" w:header="0" w:top="1134" w:footer="0" w:bottom="1134" w:gutter="0"/><w:pgNumType w:fmt="decimal"/><w:formProt w:val="false"/><w:textDirection w:val="lrTb"/></w:sectPr></w:body></w:document>

If we knew what it was we were doing, it wouldn't be called research, would it?

— Albert Einstein