File Extension INX
File Extension INX is used by Adobe InDesign as an interchange format for InDesign documents (INDD). These documents are an XML formatted representation of a complete Adobe InDesign document using the InDesign scripting DOM (Document Object Model), including all pages and content, colour information, guides, images, text frames and more. These files are compatible across versions of InDesign, except where features of a newer version have been used (such as new filters or effects). The INX files are most useful with the Save Backwards feature of InDesign to save to an earlier version. As well as Adobe InDesign, InCopy and GoLive also use INX files for interchange files, although they use a slightly different set of properties and attributes relevant to the specific application.
The Adobe InDesign scripting DOM represents each element of a document within a hierarchical tree structure with the document itself at the root. The document will have several children nodes of type Spread, Color and so on. Each of these will have their own children and also a set of attributes that define the object. For a Color object, for example, the color values, color model and the name of the color are all valid attributes. When a file is exported to INX format, all the objects in the document are translated into their XML representation along with all attributes, and when the file is read back in, a document is created in InDesign by parsing the XML and creating the corresponding objects. The INX format is an open format and is fully documented on the internet for programmers wishing to incorporate INX support into their applications. This means that a lot of programs can provide partial support for INX files dependant on which features of InDesign they support.
The file extension INX is also used on compiled scripts associated with the InstallShield software installation system. These files are not meant to be opened directly and the content is not human readable, they simply contain instructions for the installation of software packages.