Screen options are a way to customize the WordPress administrator interface to customize the display. You can edit these on different pages throughout your site using the Screen Options tab in the upper-right corner of the Administrator Interface:
Dashboard
The WordPress Dashboard is the first screen you see after logging in to WordPress. On it you’ll find both status information and links to all the administrative areas of the site. When you click on Screen Options while on the Dashboard, you can customize it with security information, Google Analytics data, or a variety of other options.
Index Pages
When clicking on any of the main navigation links, such as Posts, Events, or Pages, Screen Options will allow you to change the view for what displays in the table content, as well as the number of items that display on each page.
Individual Content Items
When editing an individual content item, Screen Options will allow you to hide or show various content elements that you may or may not need on a page. For example, if your theme is not optimized to show Author information or the Feature Images, you can uncheck those items to not display them on posts.