The Calculate Geometry geoprocessing tool calculates values into the desired field based on spatial values. You can use this tool to calculate things such as area, perimeter, central coordinates, number of vertices, and more. The exact spatial characteristics that you can calculate will be dependent on the geometry type of the features in question. For example, you cannot use the Calculate Geometry tool to calculate the area for point features because a point does not have an area.
This tool can also be used to convert units, for example, if you have polygon that was created in imperial units, but you need to know its area in square kilometers. Then you can use the Calculate Geometry tool to convert from imperial units to metric units without you knowing the exact conversation factor.
Now it is time for you to see these tools in action in a hands-on exercise.