The two sides of the design are the same.  This type of balance creates a strong statement and sets a formal tone to your design.

Line of Symmetry

With symmetrical balance, you should be able to imagine a line running right through the middle creating a mirror image. This line is called the line of symmetry.

This type of balance does not come from the sides being identical. Instead, it comes from the balance of visual interest.

There is still an invisible line, even though the sides are different.  This is a great way to add emphasis to a part of your design or to draw a viewer's eye to an intriguing element of your design.

With this type of balance the elements of your design radiate out from a central point.

Radial balance can look like a circle, a wheel, ore the spokes of a wheel. This type of balance can add depth or a feeling of motion to your design.  In architecture, radial balance is best seen in domes, frequently on the underside. 

Everything in your design is arranged siminarly without any significan variation.

This type of balance can be used to  draw attention to small details like color variation, to create a sense of regularity, or to provide a static background.