Umbraco is an open-source content management system platform for publishing content on the World Wide Web and intranets. It is written in C# and deployed on Microsoft based infrastructure. Since version 4.5, the whole system has been available under an MIT License.
More information about Umbraco can be found on the main Umbraco website.
Community provided support and documentation can be found on our.umbraco.org.
Umbraco was first created in 2000 by Niels Hartvig and went open source in 2004. The current version is available for download on the Microsoft Web Platform Installer or directly from GitHub.
Development of Version 5, based on ASP.net MVC, was retired at the Umbraco developer conference 2012. Since then, efforts have gone into building on the more mature Version 4 and version 6, including integration of MVC, and also a rewrite of the core API. Version 7 comes with a new user interface.
It is in use on over 110,000 sites worldwide and has a strong developer community, including a number of certified partners across the globe.
The Umbraco HQ released Umbraco as a Service (Uaas) on a paid subscription plan in September, 2015.