Organizing projects into categories helps you manage your projects efficiently. For example, you can create a category for each of your clients, and add projects related to them in their respective category.
In the Projects view, drag the project from the Project menu to the Category to which you want to add the project.
Select the project that you want to delete in the Categories list.
Click the arrow to the left of the project.
Select Remove From Category.
note: If you delete a project from the All Projects list, the project is deleted from all the categories to which it belongs.