One-Line Guide is a handy feature that lets you browse the on-screen guide while you're watching TV full screen.
If you have a white universal remote, press the BLUE button. If you have a Genie remote, press ENTER. You'll see the one-line guide on the bottom of your screen. Use the UP and DOWN ARROW buttons to scroll through the channels one at a time. When you're done, press the BLUE button (or ENTER if you have a Genie remote) again to close the guide.