All dartboards are divided into 20 pie-shaped sections, also called "segments", which are numbered from 1 through 20. Right at the center of all dartboards are two small circles or narrow rings, one smaller than the other, both called the bulls-eye. The smallest circle or ring right at the center are known as the inner or double bull counting 50 points (value of 2 x single bulls). The circle just outside of the inner bull is called the outer or single bull and counts 25 points.

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