Flutter: What's the difference between these code snippets

Question

As you can see, these two code snippets are customTextWidget which returns Text(). But snippet1 uses a Stless(class), snippet2 uses a Function. When I run both of these codes, they return the same result on the screen.

snippet1

class TextWidget extends StatelessWidget{
  @override
  Widget build(BuildContext context) {
    return Text("Hello World");
  }
}

snippet2

Widget TextWidget() {
  return Text("Hello World");
}

I want to know the difference between these two snippets for creating custom widgets.