With many user-interfaces looking to be as user-friendly and simple as possible, it's no wonder that search giant, Google, has also taken a step in that direction for its search results page. The sidebar on the left for desktop browsers has been repositioned as drop-down menus located between the search bar and the search results. Thus, search results have been moved to occupy the newly-vacated real estate in order to make space for the Knowledge Graph.
Search tools is also located as a drop-down menu for those who require the more advanced tools for their searches. The update is currently only available to US users while Google is working on getting it out to the rest of the world.
Source: Google Search Blog