In the Workplace Shell, associations link data files to &link_progobjs;. 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" submenu of the &popmenu;s 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 &link_wpsobj;, 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.