What is art rock

Hey...I have to write an essay for any genre of music for my music appreciation class. I was originally going to pick prog-rock, but my teacher reccomended that I write about Art Rock. I know a bit about Art Rock, but I know this board is full of plenty of people who know a great deal more than I do. Im looking for anything you have to say on the subject. Some of the things I plan on talking about are the instruments involved, the performers general background in music, the musical content, the lyrical content, the overall sense or feeling you get from this music.

Also, shout out some bands that I should be researching. Thanks in advance to anyone helping

Check this out. Seems that art rock is a very broad genre.

I think progressive rock is a sub-genre of Art-Rock.

No, Art-Rock is subgenre of progressive rock! Well, anyway, check out this page: http://www.progarchives.com/Progressive-rock.asp
and this:
http://www.progarchives.com/Progressive-rock.asp#3

Look into Brian Eno, The Velvet Underground, Robert Fripp, The New York Dolls, etc.