# Controllers and Actions

A controller is a class whose public methods, its actions, answer requests. Learn how the default route picks one from the address, where parameters come from, and what an action can return.

![Cheat sheet: Controllers and Actions](https://fsdtrainingmedia.blob.core.windows.net/public/images/2026/11/d54567fadc0e40e49e1a3ba705a81241.webp)

- Category: ASP.NET Core
- Level: Journeyman
- Tags: 404 Not Found, Action Method, aspnet-core, Controller, c-sharp, IActionResult, Route Template
- Updated: November 3, 2026

Source: https://www.ask-codey.com/cheat-sheets/controllers-and-actions-cheat-sheet