Balance is a photography technique that involves capturing images within a frame so all parts of the image have equal visual weight. Proper balance should increase the visual appeal of a photograph. There are generally two types of balance, formal and informal.
Formal balance is symmetrical balance. To achieve this type of balance, the focus of the picture should be placed in the middle of the image, while identical or similar subjects are evenly spaced around the central point. Portraits are an example of a picture where it is best to use formal balance.
Informal balance is more indistinct in nature. In a photograph with informal balance, dissimilar elements balance each other out on either side of the frame. Informal balance can occur with objects of any size, but it is most visually appealing to have a larger object balanced out with a smaller object or several smaller objects. This type of balance usually follows the rule of thirds.
Other ways to informally balance photos include having a small area of white against a large area of black, or black against white. This principle also works with vibrant colors against neutral colors. A small area of highly textured material can also balance out an area with little texture.