This photo is of Linear perspective. This first clue, is the line in the centre of the screen that starts at the photos edge and goes of into the distance. The second, and third clues are the lines, railings, to the left and right of the centre line, railing, as they go off and fade into the distance. These three lines, the way they start at the beginning or edge of the photo and then go off into the distance, creates depth.

This photo is of Focus. It uses the the manipulation of depth of field to add depth to the photo. Having the girl at the centre at the end of the railing, and having the railings go of into the distance on the left and right of her, also gives depth to the photo. I would have liked to get her further away from me, blocking more or all of the centre door opening behind her, but these are the things you learn as you go. Learned.

This photo is of relative size. It uses the trick of depth, by putting Ryan farther away from Haitham, it makes him look much smaller then Haitham, to show the size difference to one another, or trick the size difference to one another, rather.