How do 'Images' work?

I was playing with the GUI Image - Create actions, but couldn't get anything to happen.

Would this be able to display, say, an image I designed in photoshop? I have no clue how exactly it works, how to use it, or what it actually does. Would anyone mind helping out a bit?

Thanks!

Found a thread with a link to a guide when i searched http://www.wc3campaigns.net/showthread.php?t=81637

I searched through about 10 pages. Guess I used the wrong terms

Thanks!