Asymmetry refers to a lack of symmetry, or balance, in the photograph. In an asymmetrical photograph, if the photograph were to be sliced in half, neither side would be symmetrical.
Asymmetry in photography can be a very beautiful and eye-catching technique. It can create a very thought-provoking piece of art that awakens the eye due to its imperfect balance and startles the imagination into overdrive. The human eye, when viewing art, expects to see perfection; when it is greeted instead with asymmetry, it reacts in a very emotional way. When used effectively, asymmetrical photography can be very interesting to view.
Asymmetry is a technique that falls under the umbrella of photographic composition, which is defined as the aesthetically pleasing arrangement of subject matter. In an asymmetrical photograph, the subject of interest may be placed off to the left or right of the photograph rather than in the center as might be expected.
Asymmetry is the opposite of symmetry, which often places the subject of interest in the center. Symmetrical photographs may also leave empty space in the center and place two symmetrical subjects of interest on either side of the photograph. In asymmetrical photography, these rules are inverted or even occasionally subverted.