When making an inventory of a lot of polylines the area of the polyline may be a bit too detailed. With 'Categorize' you can create a graphic overview of the areas of the polyline. The command creates layers based on categories you can define. Every layer is given a random color and is used to hatch the polylines with. That means all polylines with an area within a specified category will be hatched on the same layer. The command will create a legend along with it to show which color represents which category. You can preset the size of the legend and if you want you can also export that legend to Excel in the proces. You can find the Excel file in the same folder as the drawing you are using the command in.