The Compare Files option is available from the popup menu that is available next to each file listed in the Files relationship.

The Compare Files window contains two lists which are used to select the two files that are being compared. You select a file and another file to compare it with. If the document has multiple revisions, you can select which revision you want to select files from; this lets you compare versions of a file between revisions of a document. By default the file you launched the compare files window from is selected in the Left File menu. If the document has multiple revisions the same file in the previous revision is selected in the Right File menu. After two files are selected, click the Compare button.

Once you click Compare, the screen will queue and load both files and will then display a comparison mode. If you compare two image files, differences will be highlighted graphically using colors. If you compare two text files, a special side-by-side comparison is used to show differences.