In the Workplace Shell, associations link data files to program objects and program files. If extended file types have been enabled in the "&xwp; Setup" object, this is done entirely with the use of file types.

The type of a data file depends on two sources:

If a program object has been associated with a file type, the program object appears in the "Open" context menu of all data files which have that type. The first association determines the icon of the data file and is also used when you double-click on the file.

In the above example, if you now associate the "Acrobat PDF" type with the program object for the Adobe Acrobat Reader, all files matching *.PDF can be opened with that program object.

In addition, file types may inherit from each other. You can define those parent-child relationships on the "File types" page in the "Workplace Shell" object, simply by dragging the file types around. If a type has thus been made a child of another type, the associations for the parent type will also be available for all data files of the child type.

For example, assume that you also have defined a "PostScript" file type. Since PDF documents are really special PostScript files, you can make "Acrobat PDF" a child type of "PostScript". If you have, say, a GhostScript association for the "PostScript" type, your PDF files can then also be opened with the GhostScript program.