ASP.NET MVC is a web application framework developed by Microsoft that implements the model–view–controller (MVC) pattern. It is no longer in active development. It is open-source software, apart from the ASP.NET Web Forms component, which is proprietary. ASP.NET Core has since been released, which unified ASP.NET, ASP.NET MVC, ASP.NET Web API, and ASP.NET Web Pages (a platform using only Razor pages). MVC 6 was abandoned due to Core and is not expected to be released. Core is currently planned to merge into ".NET 5".