The usage analytics reports show how visitors have interacted with the content on your website, for example which item has been viewed the most. The reports are broken down per usage event. This means that by default you’ll be able to see:
SharePoint Server 2013 creates two usage analytics reports:
Both of these reports are automatically updated once every 24 hours. For more information go to Microsoft's View usage reports page.
If you want to see number of views on a particular item in a document library, just click on the ellipsis to the right of the document. You will see the number of views in the upper right of the dialog box, as shown in this screenshot.