# Backend & Custom Logic

- [Controllers](https://docs.umbraco.com/umbraco-cms/18.latest/develop-with-umbraco/application-code/backend-and-custom-logic/controllers.md): An Umbraco API Controller is an ASP.NET WebApi controller that is used for creating REST services.
- [Routing](https://docs.umbraco.com/umbraco-cms/18.latest/develop-with-umbraco/application-code/backend-and-custom-logic/routing.md): All about Umbraco's routing pipeline & the types of Controllers used in Umbraco
- [Controller & Action Selection](https://docs.umbraco.com/umbraco-cms/18.latest/develop-with-umbraco/application-code/backend-and-custom-logic/routing/controller-selection.md)
- [Custom MVC Controllers (Umbraco Route Hijacking)](https://docs.umbraco.com/umbraco-cms/18.latest/develop-with-umbraco/application-code/backend-and-custom-logic/routing/custom-controllers.md): Use a custom MVC controller to handle and control incoming requests for content pages based on a specific Document Type, also called Route Hijacking.
- [Custom Middleware](https://docs.umbraco.com/umbraco-cms/18.latest/develop-with-umbraco/application-code/backend-and-custom-logic/routing/custom-middleware.md): Customizing the ASP.NET middleware pipeline in Umbraco
- [Custom MVC Routes](https://docs.umbraco.com/umbraco-cms/18.latest/develop-with-umbraco/application-code/backend-and-custom-logic/routing/custom-routes.md): Setting up your own controllers and routes that exist alongside the Umbraco pipeline.
- [Execute Request](https://docs.umbraco.com/umbraco-cms/18.latest/develop-with-umbraco/application-code/backend-and-custom-logic/routing/execute-request.md)
- [Request Pipeline](https://docs.umbraco.com/umbraco-cms/18.latest/develop-with-umbraco/application-code/backend-and-custom-logic/routing/inbound-pipeline.md)
- [Routing in Umbraco](https://docs.umbraco.com/umbraco-cms/18.latest/develop-with-umbraco/application-code/backend-and-custom-logic/routing/request-pipeline.md): What the Umbraco Request Pipeline is
- [FindPublishedContentAndTemplate()](https://docs.umbraco.com/umbraco-cms/18.latest/develop-with-umbraco/application-code/backend-and-custom-logic/routing/request-pipeline/find-publishedcontent-and-template.md)
- [IContentFinder](https://docs.umbraco.com/umbraco-cms/18.latest/develop-with-umbraco/application-code/backend-and-custom-logic/routing/request-pipeline/icontentfinder.md): Information about creating your own content finders
- [Inbound Request Pipeline](https://docs.umbraco.com/umbraco-cms/18.latest/develop-with-umbraco/application-code/backend-and-custom-logic/routing/request-pipeline/inbound-pipeline.md): How the Umbraco inbound request pipeline works
- [Outbound Request Pipeline](https://docs.umbraco.com/umbraco-cms/18.latest/develop-with-umbraco/application-code/backend-and-custom-logic/routing/request-pipeline/outbound-pipeline.md): Learn how the Umbraco outbound request pipeline works.
- [Published Content Request Preparation](https://docs.umbraco.com/umbraco-cms/18.latest/develop-with-umbraco/application-code/backend-and-custom-logic/routing/request-pipeline/published-content-request-preparation.md): How Umbraco prepares content requests
- [Special Property Type Aliases for Routing](https://docs.umbraco.com/umbraco-cms/18.latest/develop-with-umbraco/application-code/backend-and-custom-logic/routing/routing-properties.md): Describes special property type aliases which can be used to customise routing
- [Surface Controllers](https://docs.umbraco.com/umbraco-cms/18.latest/develop-with-umbraco/application-code/backend-and-custom-logic/routing/surface-controllers.md): Information about Surface Controllers in Umbraco
- [Surface Controller Actions](https://docs.umbraco.com/umbraco-cms/18.latest/develop-with-umbraco/application-code/backend-and-custom-logic/routing/surface-controllers/surface-controllers-actions.md): Information about Surface Controller Actions Result Helpers in Umbraco
- [Umbraco API Controllers](https://docs.umbraco.com/umbraco-cms/18.latest/develop-with-umbraco/application-code/backend-and-custom-logic/routing/umbraco-api-controllers.md): A guide to implementing APIs in Umbraco projects
- [Porting Old Umbraco API Controllers](https://docs.umbraco.com/umbraco-cms/18.latest/develop-with-umbraco/application-code/backend-and-custom-logic/routing/umbraco-api-controllers/porting-old-umbraco-apis.md): Tips to porting over API controllers from Umbraco 13 and below
- [URL Rewrites in Umbraco](https://docs.umbraco.com/umbraco-cms/18.latest/develop-with-umbraco/application-code/backend-and-custom-logic/routing/iisrewriterules.md)
- [URL Redirect Management](https://docs.umbraco.com/umbraco-cms/18.latest/develop-with-umbraco/application-code/backend-and-custom-logic/routing/url-tracking.md): URL redirect management in Umbraco
- [Subscribing to Notifications](https://docs.umbraco.com/umbraco-cms/18.latest/develop-with-umbraco/application-code/backend-and-custom-logic/subscribing-to-notifications.md): Subscribing to notifications allows you to listen to specific events and run custom code in response.
- [Inversion of Control / Dependency Injection](https://docs.umbraco.com/umbraco-cms/18.latest/develop-with-umbraco/application-code/backend-and-custom-logic/using-ioc.md): Inversion of Control/Dependency Injection in Umbraco
- [Service APIs](https://docs.umbraco.com/umbraco-cms/18.latest/develop-with-umbraco/application-code/backend-and-custom-logic/umbraco-services.md)
- [Creating Forms](https://docs.umbraco.com/umbraco-cms/18.latest/develop-with-umbraco/application-code/backend-and-custom-logic/creating-forms.md): Information on creating forms in Umbraco
- [Source Control](https://docs.umbraco.com/umbraco-cms/18.latest/develop-with-umbraco/application-code/backend-and-custom-logic/source-control.md): In this article you can learn more about how to effectively source control your Umbraco site.


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