A statistic that measures the number of walks a batter has, divided by the number of times he has struck out. The higher the ratio, the more disciplined the hitter, and the better knowledge he has of the strike zone.
In the statistical analysis of baseball, this stat is a good measure of a batter's discipline at the plate, as well as the inherent knowledge he has of his strike zone. In general, hitters with good BB/K ratios must not only show the discipline and patience to not swing at poor pitches, but also be able to recognize when a pitch may be called a strike and swing accordingly, either for a hit or to foul it off.
Two of the highest career BB/K ratios are held by Wade Boggs and Joe Morgan, and it's no coincidence that they are regarded as two of the better hitters of their generation. When a batter is hit by a pitch it is not considered a walk; therefore it is not considered part of the BB/K ratio.