Anatomy of an Office Theme
Office themes are saved with a file extension of THMX which is part of the OpenXML standard, which was introduced with Office 2007 and carried through to Office 2010. A THMX file is also referred to as a ZIP file because it includes an embedded hierarchy of folders and various XML files that describe the contents of the overall THMX file. OpenXML enthusiasts can directly modify the contents of a THMX file by adding a ZIP suffix to the THMX file, for example PowerPointFileName.THMX.ZIP. You can then extract the THMX file contents to a location on your computer.
Listing 18.1 shows the initial section of the .THMX embedded theme.xml file that is located within the extracted theme\theme\theme.xml file. Note the