Umbraco is written in C# and built upon Microsoft's .NET Framework, Microsoft SQL Server, and XSLT, a XML-based language used for the transformation of XML documents. It is designed to be a toolkit for building custom software. It is easy to use, simple to understand, and is highly extensible using industry-standard languages and patterns such as HTML, CSS, Razor, MVC and jQuery.
Inspite of offering all the benefits of an enterprise level web content management system, Umbraco CMS for being an open source, has no license cost. What gives it the cutting edge is the presence on an active and fast-growing community of devoted developers worldwide. They provide massive support right from fixing bugs quickly to contributing new features to the system on a regular basis.
Because of its no-cost, open-source licensing, simplicity and its unlimited potential, Umbraco hasbeen driving websites covering multiple languages across myriad industries.
Clean intuitive interface and is not overloaded with unnecessary features
Easy framework that allows multiple websites to run on the same installation
Multi-language support, Quick data retrieval provision and great extensibility
Short learning curve allows a developer to build websites incredibly quickly.