Balance is
- an element of design that concerns how well design elements (e.g., color or size) are distributed across a composition, a text
- an aesthetic judgement regarding how well design elements are placed in relation to one another.
Symmetrical Balance is when design elements on the the left side of an image mirror the design elements on the right side, or the top mirrors the bottom of the composition.
Asymmetrical Balance is when one part of a text is heavier or lighter than another part of the text—i.e., when more textual elements, especially color or copy, are used in one quadrant of a composition than other parts of the text.
Radial Balance is when textual elements flow from the center of a text.