The word portraiture is used to describe a particular category of art which dates back to ancient times.
The purpose of a portrait is to memorialize an image of someone for the future. It can be done with a number of mediums. The human body and face are fascinating subjects that many artists like to study in their personal work.
”If what I feel about life is not in a print of mine, then I might just as well say that any machine can take a picture and turn out a print mechanically. You might get wonderful pictures as a result, but they would not contain that something called love or passion, both of which are the essentials needed to bring forth a living print—or any other living creative expression.” - Alfred Stieglitz