With Family Tree Builder you can build your family tree, add photos and associate those photos to persons in your tree.
If you click on a person's name in the tree, it will bring up all the photos related to that person. This is very handy for quick searching. It is also a great way for future generations to identify their ancestors.
In addition the program "learns" to recognize faces in photos after you've taught it a few times who a person is in the photo. It does this using the same technology used in Face Recognition with celebrities.