Weight vs. Volume
Various factors can yield different quantities when measuring by volume, such as a cup of nuts loosely poured compared to a cup that is tightly packed with small or broken pieces. That's why weighing ingredients can make a real difference in the successful outcome of your recipe.
Consider the following factors in choosing a scale: For greater accuracy in small quantities, and for the greatest versatility, choose an electronic scale. For regular kitchen use, a 6-9 Lb capacity scale will suffice on most tasks. If you're measuring ingredients for dietary needs, choose the electronic or the diet scale.