Any time a document is viewed, modified, deleted or restored this action is recorded. To view the recorded history of a document, click on the document you wish to explore. Once this has loaded in the preview window click the ‘History’ button on the top bar.
You will be presented with a list of all actions regarding this document since the documents creation. Clicking on an action will reveal more information on the action such as when the change was made, what the change and who made the change.