Node viewer window is missing when i go into 'shading' I'm following a tutorial video on youtube and when the guy goes into the shader mode, his screen shows the main window, then below that a window in which the nodes that he's playing around with are located. There are also two windows to the left that show files (at the top) and some sort of viewing window (bottom). 

When I open it I see the main window, the two side windows but no node editor/viewer window. Please see screenshot below. 

I've been searching for how to bring the window up for over an hour and no luck.

Someone please tell me how to set my shader mode so that the node window appears at the bottom of the screen.
You can change any window to any view.

Drag out a new window,
On the top left corner, Editor Type icon, choose Shader Editor.

P.S. I had the same problem before. lol