I have seen the "BROWSE" tab in SharePoint 2013 pages and lists etc.. some pages are not showing browse tab.I am not sure , what is the use of this.
Suggest an information about Browse tab.
Browse tab is particularly useful when you have top navigation enabled. Browse tab hides the ribbon and shows the top navigation. Hope this helps.
The purpose of this tab is hiding of the most Ribbon interface in page read mode - when the Ribbon isn't needed.
When the Browse tab is displayed the Ribbon gets minimized for saving of useful page space. The height of the Ribbon is reducing to the height of tabs headers area.