One of the biggest changes to Windows 7 is the Cortana bar at the bottom
This is a great way to search for items on your computer, such as programs, documents, and even settings. You can also use this to search the web.
By default, Chrometana will open a Bing search. To change this, do the following:
For a more visual help, watch the following video (it is a little outdated, but still works):