Wallpaper = A covering that has all kinds of designs on it. As you see on the wallpaper, there are no designs but it does have color.
Book covers = A book cover protects the book. The covering shows pictures which describes what kind of book it is.(Ex:) As you can see on the cover of the book, a color background but in the foreground is a tree and a mockingbird.
Wrappers = a piece of paper or can be plastic that might have some words or color to it. (Ex:) The wrapper has words on it with a blue background along with a black and white cookie in the foreground.
I hope I helped you and if you want to edit these answers, you can but these are my examples. :)