When you click on 'View', a drop-down menu appears.

'Preview Quality':

The display quality of the document can be chosen as either 'Low' (faster, proxy images used) or 'High' (renders high-resolution images). This is mainly noticable when zoomed in on the document.

'Preview Edit Content Rules':

This option allows you to preview the document with the defined 'edit' content rules in action. This will simulate the view that an editor would have of the document.

'Preview Review Content Rules':

This option allows you to preview the document with the defined 'review' content rules in action. This will simulate the view that a reviewer would have of the document.

'Preview Frame Rules':

This command allows you to preview the defined frame rules that would be available to an 'Editor'.