How is navigation link management and storage handled within UINavigationController?

UINavigationController manages a stack of view controllers, where each new screen is placed on top of the previous one. Navigation links are stored in the viewControllers array, which represents the stack.

When you call pushViewController:animated:, a new controller is added to the end of the stack, and when you call popViewControllerAnimated:, the top controller is removed, returning the user to the previous screen.

Example:

// Add a new screen
navigationController?.pushViewController(detailVC, animated: true)

// Go back
navigationController?.popViewController(animated: true)

// Get the current stack of controllers
let stack = navigationController?.viewControllers

Thus, UINavigationController provides convenient management of app screen navigation through a stack of controllers.