Windows 8 Split Screen Viewing
While Metro-style apps run in full screen mode, you can get two Metro-style apps (or one Metro-style app and one classic app) running side-by-side. This requires a screen with at least 1366 pixels horizontally, and you can change the ratio of onscreen size that each app gets using a simple slider. To get started, just 'touch' the left side of your screen with both applications running, then click and hold the 2nd app and drag it to the right & release the mouse button.
For more Windows 8 information see http://www.HelpWithWindows.com/Windows8/