C# .NET - Host Configuration vs App Configurations - Difference and similarities

Program.cs

class Program
{
    static void Main(string[] args)
    {
        CreateHostBuilder(args).Build().Run();
    }

    private static IHostBuilder CreateHostBuilder(string[] args)
    {
        return Host.CreateDefaultBuilder(args)
            .ConfigureHostConfiguration(configHost =>
            {
                configHost.SetBasePath(Directory.GetCurrentDirectory());
                configHost.AddJsonFile("hostsettings.json", optional: true);
                configHost.AddEnvironmentVariables(prefix: "MYDEMOAPP_");
                configHost.AddCommandLine(args);
            })
            .ConfigureAppConfiguration(app =>
            {
                app.AddJsonFile("appsettings.json"); ;
            });
    }
}