Diff between accuracy and precision??

Accuracy refers to how close measurements are to the "true" value, while precision refers to how close measurements are to each other. Maybe this example can help to further show the differences. Let’s talk potato chips! Suppose you’re a snack foods manufacturer producing 12 oz. bags of potato chips. You test the weight of the bags using a scale that measures the bags precisely (in other words, there is little variation in the measurements), but not accurately – measuring 13.2 oz., 13.33 oz., and 13.13 oz. for three samples. Or maybe the scale is accurate, measuring the three samples at 12.02 oz., 11.74 oz., and 12.43 oz., but not precise. In this case, the measurements have a larger variance, but the average of the measurements is very close to the target value of 12 oz. Or maybe your measurements are all over the place, with samples measuring at 11.64 oz., 12.35 oz., and 13.04 oz., in which case your scale may be neither accurate nor precise.