Negative space is the area not occupied by positive space items (often backgrounds like sky, simple landscapes, etc.).
Artists and photographers can arrange the positive and negative space in their pictures to emphasize the picture’s storytelling and to create interesting compositions.
The two main terms describing how subjects are arranged or “balanced” within a picture are “symmetrical” and “asymmetrical”
Symmetrical balance is where the subjects are arranged so that they are in the middle of the picture frame or are even distributed throughout the frame.The subjects in a picture with asymmetrical balance are distributed in an uneven pattern.
Here’s another way to think about balance in a picture - imagine the bottom of the picture frame as the surface of a see-saw or teeter-totter with a fulcrum under the middle.
Now imagine all of the subjects in the picture frame falling straight down onto the surface of the teeter-totter. If the teeter-totter stays level, you have symmetrical design. If the teeter-totter drops to one side, you have an asymmetrical design.
Keep in mind that the further away form the center/fulcrum an object is, the more downward pressure it will exert on the teeter-totter. So, a large object near the center of the frame might be counterbalanced by smaller objects positioned farther to the opposite side of the frame.
Symmetrical designs often impart a feeling of formality, stiffness or solemnity. Asymmetrical design can impart a very wide range of feelings.
There is a sub-category to asymmetrical design – the seemingly oxymoronic “balanced asymmetrical design”. This is where the subjects are arranged asymmetrically within a picture but would still not cause the teeter-totter to tip.
It’s good to be aware of these types of design balance when producing photos, illustrations or sequential media (comics, storyboards, film, etc.) If you are producing sequential media, it’s usually a good idea to mix the various balance types in order to get keep things visually interesting.
These panels by an un-credited Chinese comics artist show great design. It’s easy to see the positive and negative space in these frames! The frame on the top is asymmetrical design while the one on the bottom looks like it could be asymmetrically balanced.