Project window allows you to organize your project files which you can use if you feel the need to
Open the Project window from the View menu / Project / Project or by clicking the Project button in the Debug toolbar.
Project root with current target
When a new project is created, a Target named Debug is generated automatically.
Collection of project files (Info, Linker files, Source files, Dependencies). Every Group exists in every target and groups the same project files. Besides being a visual aid in browsing project hierarchy, group names can be used in the link process. Groups do not have compilation and assembly settings, output directories etc.
winIDEA divides project files by their extension into four types:
External libraries and framework.