Running two apps side by side
Any app can be pinned to the left or right-hand side of the screen. For example, open the People app and then press the Windows Key + . (period) to move that app to the right-hand side of the screen, pressing the same keys again will move it to the left-hand side, and pressing the same keys again will make it full screen. While an app is pinned, any other app or program can be opened and loaded into the available space on the screen. For example, in the below picture, we've opened a browser window and have the People app running to monitor our social networks.
Any open app can also be pinned using your mouse by clicking at the top of the tile and dragging it to the left or right-hand side of the screen.
Bonus tip: The Desktop can also be pinned to the left or right-hand side of the screen.
Note: In order for snap to work properly your resolution must be at least 1,366 x 768.

Windows 8 Task Manager
The Windows 8 Task Manager has been significantly improved over previous versions of Windows. Some of the new changes include showing a total percent usage at the top of your Processes, which makes it easier to determine total memory and CPU usage, improved Performance graphs, a Startup tab to see startup processes and their impact to system performance, and the App history tab (as shown below) that gives you the total resources an app has used over a period of time. Press Ctrl + Shift + Esc to start exploring the new Task Manager.