Google: Search with Omnibox

An Omnibox is similar to the traditional browser address bar with additional features. For example, in the Google Chrome browser, the Omnibox (address bar) not only displays the address of the web page you are using, but also can be used to search the Internet. As seen in the picture, the Omnibox in Chrome can also perform mathematical calculations and even answer questions such as "how many cups are in 2 liters?"

Reference:
Omnibox
http://www.computerhope.com/jargon/o/omnibox.htm