In order to find and try to decipher the silence, people make art from one another to portrait emotions, feelings, moods etc that can't be portrait with something that's not alive. Trying to talk about humans in a photo is more interesting in my opinion than talking about a landscape. You could see the expressions and their unique human characteristics giving you more hints as to how old he or she might been what they might do, they class, etc. In comparison to a landscape its a little less descriptive and narrower to the imagination, how ever in my opinion if a photograph of a person is well composed as in also portraying its setting and environment, then is a story.
An artist main intention is to try to get his thought across to his audience, to show what is going on, to portray it in a single frame. For this reason portrait artist might talk about what is happening with their subjects, or how the subject can relate to his main idea as an important part of it.
Photographic portraits are different than other mediums because now they can show more detail specially during this times in which technology it's so advance that the cameras that are made have very high megapixels which are perfect for portraits. One can even see a single hair strand in a picture which is something very awesome. On the other hand if using paint as a medium one will not be able to notice as much details as possible in comparison to digital photography. Also when using film or black and white pictures it gives the image a different feeling and sort of puts more focus into the subjects that the artist is trying to present.
