Taking Screenshots
Sceenshots can be taken simply by pressing "PrtScrn" (Print Screen) key.
To capture certain area press and hold "shift" and then press"PrtScrn" key
that is shift+PrtScrn
It doesn't work at some places.
For that you can set timer for screenshot and then do whatever you want and let the system take Screenshot. (Explained later)
Screenshots Folder
If you are loggen in as Root user default save directory of screenshots is "/" .
That means directly in your local drive.
If you are logged in as any other user except ROOT. Then it might not save screenshot at all. So you will have to set the screenshot folder First. or you can use this method to know where system is saving screenshot
1] Install
dconf-editor
(If you dont have it already)
Terminal command
sudo apt-get install dconf-editor