The Grails Framework 5.2.4

(Quick Reference) ### Controller Usage A controller fulfills the C in the Model View Controller (MVC) pattern and is responsible for handling web requests. In Grails a controller is a class with a name that ends in the convention "Controller" and lives in the `grails-app/controllers` directory. A controller can be created with the create-controller command:
    grails create-controller org.bookstore.hello
or with your favourite IDE or text editor.
    package org.bookstore

    class HelloController {

        def world() {
            render "Hello World!"
        }
    }
Each action in the controller is a method or a Closure and it has access to a number of implicit variables and methods. Refer to the user guide topic on Controllers for more information. | Quick Reference (hide)