Magento2 Module 만들기

1. create Folder named as Webdev inside app/code
2. create Folder named as Helloworld inside app/code/Webdev
3. create Folder named as etc inside app/code/Webdev/Helloworld
4. create new file named as registration.php inside app/code/Webdev/Helloworld
   기본 코드

<?php
\Magento\Framework\Component\ComponentRegistrar::register(
	\Magento\Framework\Component\ComponentRegistrar::MODULE,
	'joosun_Helloworld',
	__DIR__
);
?>

5. create new file named as module.xml inside app/code/Webdev/Helloworld
6. Run Commands:
   php bin/magento setup:upgrade
   php bin/magetno setup:compile
   php bin/magento setup:static-content:deploy-f