If they display on your computer screen is sideways or upside down, you can easily turn the display back to the regular upright position very easily. This video will show you how to simply restore your display to the correct position.
You can try pressing the CTRL button along with the UP/DOWN arrow keys to see if that will bring it back (you might need to also try the left and right arrow keys if that doesn't work). Failing that go into Control Panel and look for your graphics card control panel (If you have an NVidia card it will be NVidia Control panel, if you have an ATI card it will be something like ATI Catalyst.). Click on your graphic card control panel icon and once the graphics card control panel has opened look for an option to 'Rotate the display'. You will then be able to change the display from portrait to landscape.
![](https://i.ytimg.com/vi/Kkt1GNaZYcc/mqdefault.jpg)