Carat weight is simply a measure of weight and is how we determine the size of a diamond.
Larger diamonds are rarer than smaller ones making them more valuable and expensive than a smaller one of the same cut and clarity.
One carat is divided into 100 points, as an example, we refer to a half-carat as a fifty pointer based upon its exact weight to the one hundredth of a carat.
Think of the points in a carat the same as you would cents in a dollar.
For more information on Carat Weight, take a look at our videos on the 4C's.