Photoshop :: Thumbnails Instead Of Cascade?

I used to work on Photoshop Elements and would generally have around 20 images / files open that I was manipulating. 

They would appear at the bottom of the screen as thumbnails so I could easily chop and change from each one.  

Now I have the full blown photoshop and can only seem to cascade each image / file I have open as tiles on the screen. 

Is there a way to have them as thumnails down the bottom so thay are all permanently visible?