Balance: The distribution of the visual weight of objects, colors, textures and space. If the design was a scale, these elements should be balanced to make a design feel stable. In symmetrical balance, the elements used on one side of the design are similar to those on the other side; in asymmetrical balance, the sides are different but still look balanced. In radial balance the elements are arranged around a central point and may be similar.
Examples of Symmetrical, Asymmetrical and Radial Balance:
Example 1: A-Symmetrical

Example 2: Radial

Example 3: Symmetrical

Example 4: A-symmetrical

Example 5: Radial

Example 6: A-symmetrical

Example 7: Symmetrical