We’re going to build a very simple module in Magento 2. When finished, the module’s output will say “Hello world!” in the block content on a custom frontend route.
Controllers in Magento 2, like on other PHP MVC frameworks, are important part of Mvc flow. In Magento 2 there are lots of changes in controllers, for example; how they are structured and how they work compared with Magento 1. If you are familiar with Magento 1 controllers, then you know they can have multiple actions (class methods). In Magento 2 controllers have only one method (execute) that will be called by front controller. This article covers controller basics, matching flow, controller types (admin and frontend), changes on existing controllers, instructions to create custom controllers and an example how to create a few controllers.