import 'package:flutter/material.dart';

void main() => runApp(HelloWorldApp());

class HelloWorldApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {

    //MaterialApp acts as a wrapper to the app and 
    //provides many features like title, home, theme etc   
    return MaterialApp(
      title: 'Hello World App',

      //Scaffold acts as a binder that binds the appBar,
      //bottom nav bar and other UI components at their places     
      home: Scaffold(

        //AppBar() widget automatically creates a material app bar
        appBar: AppBar(
          title: Text('Hello World App'),
        ),

        //Center widget aligns the child in center
        body: Center(
          child: Text('Hello World'),
        ),
      ),
    );
  }
}