The playlist items can be marked with categories of the specified color to visually differentiate types of content like commercial items, TV ratings, etc.

The category can be defined for each individual playlist item. For this click within the "Category" cell of the playlist item, the drop-down list with default categories will be shown:

custom_category_applying

Select the category you want to apply for this item.

To delete the applied custom category, select "No category" for this item.

The custom categories are created via the "Preferences" dialog.

Important
Refer to this paragraph to learn how to create custom categories.