(1) An LCD screen on a digital camera that is viewed to frame and shoot pictures, not just display them after they have been taken.  See 
viewfinder.
(2) A view of the final version of a document.  Most applications automatically provide a live preview.  As you make changes to the data on the page with regard to fonts, colors, placement, etc., the changes occur in real time.  However, some applications offer a live preview mode that lets users quickly see how the changes would look before applying them.  See 
WYSIWYG.