If you want to see the revisions of an object, you should first turn on in the menu and expand the tree view of that particular file. In this view, a file is not a simple flat file, but rather a container of various sorts of information, including its revisions.
The revisions of a document are stored in a subfolder named 'Document Revisions'. The revisions of a model are stored directly in the folder with the name of the model. The revisions of a DID are stored directly in the folder with the name of the DID. The revisions of a Text Block are stored in a folder with the name Text Block revisions, the revisions of a Form are stored in a folder with the name Form revisions, the revisions of a View are stored in a folder with the name View revisions and the revisions of a Field set are stored in a folder with the name Field Set revisions.
A number identifies a revision and in the tree view they are ordered with the most recent revision on top. In the content pane you can order revisions in other ways by clicking on the headers of the shown list. You can double click a revision to view it.
From every revision the ITP/MDK Repository will show its number, when it was changed, who created it and from which revision it has been derived.