Laravel, Booted vs hasBeenBootstrapped?

class Application extends Container implements ApplicationContract, HttpKernelInterface
{
    /**
     * The Laravel framework version.
     *
     * @var string
     */
    const VERSION = '5.5.34';

    /**
     * The base path for the Laravel installation.
     *
     * @var string
     */
    protected $basePath;

    /**
     * Indicates if the application has been bootstrapped before.
     *
     * @var bool
     */
    protected $hasBeenBootstrapped = false;

    /**
     * Indicates if the application has "booted".
     *
     * @var bool
     */
    protected $booted = false;
}