Windows 8.1 allows to open multiple apps in a single screen in 50-50 share or with other ratios. This makes working very easy as you wont need to switch from one screen to another and 2 screens can be viewed simultaneously. Th following tutorial will help you to know about docking and undocking of Apps in Windows 8.1
Steps to Dock and Undock Apps in Windows 8.1
1. Open an App from the Start Screen. Take the cursor to the tp, drag it like shown in the figure.
2. Drop the window to the right only when a boundary appears on the middle of the screen.
3. Open another App.
4. Move the divider to the right ot left to adjust the space.
5. To exit multi app mode, drag the divider top the extreme right or left.