In the Xcode, you have three separate areas of working - Navigators (in red), Debug area(in green) and Utilities(in blue).

The workspace window always includes the editor area. When you select a file in your project, its contents appear in the editor area, where Xcode opens the file in an appropriate editor. For example, in the image above, the editor area MainViewController.swift, a swift code file that is selected in the Navigator area on the left of the workspace window.

Navigator Area

The navigator window contains the following eight options:

• Project navigator. Add, delete, group, and otherwise manage files in your project, or choose a file to view or edit its contents in the editor area.
• Symbol navigator. Browse the symbols in your project as a list or hierarchy. Buttons on the left of the filter bar let you limit the shown symbols to a combination of only classes and protocols, only symbols in your project, or only containers.
• Find navigator Use search options and filters to quickly find any string within your project.
• Issue navigator. View issues such as diagnostics, warnings, and errors found when opening, analyzing, and building your project.
• Test navigator. Create, manage, run, and review unit tests.
• Debug navigator. Examine the running threads and associated stack information at a specified point or time during program execution.
• Breakpoint navigator. Fine-tune breakpoints by specifying characteristics such as triggering conditions.
• Report navigator. View the history of your build, run, debug, continuous integration, and source control tasks.

The Editors

Most development work in Xcode occurs in the editor area, the main area that is always visible within the workspace window. The editors you use most often are:

• Source editor. Write and edit source code.

  

• Interface Builder. Graphically create and edit user interface files.

  

• Project editor. View and edit how your apps should be built, such as by specifying build options, target architectures, and app entitlements.

  

Configure the editor area for a given task with the editor configuration buttons on the right side of the toolbar: