You can use working sets to group resources so that you can work on a set of resources instead of working with the entire project. When you select a working set, only the resources contained in the defined set appear in the Project Explorer view.

You can use a working set to build a set of resources of your project, instead of building the entire project. To build resources using a working set, you must first define a working set with the resources that you want to include in the build.