As a part of contemporary professional photography, especially for portraits ( bridal, engagement, seniors, etc. ) or special events, such as weddings, collages of images have often times become the favorites of brides and grooms, etc.  Most full service photography studios and businesses now offer these and it is a specialty of Andreia Brandon of Brandon Imaging.  Having recently recorded a senior portrait in two sessions, one casual and one more formal, what you are seeing here is an  example of a collage image, where individual images are digitally processed and blended into one.