If a part of a disgined is emphasized, what is ment to do?

Its meant to be seen and to show importance

Explanation:

Its like a sentence, when someone emphasizes a word, it shows the importance of that word in the sentence, so if an artist darkens a certain part of a picture or makes it bold to emphasize it, then it means the emphasized part is important to the picture and the story.  

jan tschichold, the son of a designer and sign painter

violins play the melody in this section of sergei prokofiev's peter and the wolf.

hope this !