With the release of Business Central OnPremise one major change they introduced is the UI of the web client. It is same UI which was released earlier for Business Central Cloud Version. It has rich interface and the look and feel is way different then earlier versions
We always used to use the search for finding pages/reports but with new search they have broadened the scope and now can search can be used to find the actions available on that page. As shown below on the Sales Order Page, when I search for post it displayed the actions with that name and also other pages. You can directly launch those actions from this page or open other pages.
The new search is called “Tell Me” and you can access Tell Me from anywhere from the application and the keyboard shortcut is Alt+Q
This is a great improvement and very useful when you have lot of actions on a page.