According to Wikipedia - a portrait is:
A portrait is a painting, photograph, sculpture, or other artistic representation of a person, in which the face and its expression is predominant. The intent is to display the likeness, personality, and even the mood of the person. For this reason, in photography a portrait is generally not a snapshot, but a composed image of a person in a still position. A portrait often shows a person looking directly at the painter or photographer, in order to most successfully engage the subject with the viewer.
There are a lot of photographers who trz to do something new. One of them is Nick Turpin an experienced editorial, design and advertising photographer shooting for international clients from bases in London and near Geneva.
Nick generally works in public places either as a street photographer capturing the more unusual moments of everyday life or with his assistants shooting location lit portraits of strangers.
One of his portfolios is: Portraits of strangers