These are automatically generated sitelinks that allow you to show more relevant pages to your (future) customers, making you save time, and work.
But keep in mind that the dynamic sitelinks only show up when they are likely to perform better than your regular sitelinks, so don’t stop optimizing your sitelinks!
Find out more about the subject here: https://support.google.com/adwords/answer/6058574
Or alternatively, visit : www.blue2purple.com