Accuracy is like having a range, from this to that, that your results fall in, while precision is producing the same result in repeated trials. Accuracy would be like shooting arrows at a target. The new Pixar movie "Brave" has a scene where suitors for the maiden are demonstrating their archery prowess by shooting at a target. The best archers are able to hit the target body, albeit in different places. That would be accuracy, the ability to hit the target, although within different spots on the target. The maiden, deciding to compete herself, demonstrates precision by landing an arrow squarely in the center of the target, known as a "bulls-eye", and then shooting another arrow that splits the first arrow in half. That is the definition of precision, to be able to produce the same results in successive trials. Think about the law of gravity; you get the same result every time you test the law of gravitational attraction on an object.