Orchard is a free, open source, community-focused Content Management System built on the ASP.NET MVC platform. All components in Orchard can be replaced or extended. Content is built from easily composable building blocks. Modules extend the system in a very decoupled fashion, where a commenting module for example can as easily apply to pages, blog posts, photos or products. A rich UI composition system completes the picture and ensures that you can get the exact presentation that you need for your content.