Have a look at these key art montages illustrating how key art is so stereotypical!
Most of the time آپ can tell the genre of a movie سے طرف کی just glancing at the poster.
There are 10 تصاویر in the series link
for full viewing.
ex: مالٹا, نارنگی on black and white is action and crime
I think its the kind of thing آپ dont really notice until آپ see the comparison. wow.