Moonlight: Web Applications for All Systems

Moonlight is a portable version of Silverlight running Windows, Linux and MacOS. It provides a platform for developing rich web applications.

It is written in C++ one-third and C # two-thirds. It depends on Mono, Cairo for the rendering engine, GTK + for the graphics library.
On Linux and MacOS, it is enough to install a Firefox plugin to integrate the Mono virtual machine. Windows will have Silverlight installed instead.

Interest in this framework faded significantly into the background over time, even more than in the original, Silverlight, more or less discarded by Microsoft, because universal compatibility can be achieved more directly with HTML 5 and JavaScript frameworks. And the future of development, seemingly focused on tablets and smartphones, tactile frameworks for mobile are also the best alternative.

Updated May 2012:

On May 29, 2012, Miguel de Icaza announced the completion of Moonlight:

Silverlight did not achieve significant adoption on the Web, so it did not become the technology that needed to be used, and I thought it would.
And Microsoft has added restrictions to Silverlight that make it useless for desktop programming.
Currently, we no longer believe that Silverlight is a platform that is suitable for write-once-run-anywhere technology.

Moonlight 2.0

Version 2.0 corresponds to Silverlight 2 with a part of Silverlight 3, and has been available since December 17, 2009. This is a complete break with version 1.0, when there will be few differences for version 3.
It includes a web-limited version of the Microsoft CLR, allowing languages other than JavaScript.
Deep Zoom provides a magnifying glass effect for images .

Other implementations added:

Moonlight 3.0

It offers support for H.264 and AAC video codecs.

Moonlight 4

Since an agreement was made between Microsoft and Novell for a port of Silverlight 4 running Mono, version 4 of Moonlight was developed. In 2012, a beta version is available for download (see below). Please note that we are in Silverlight 5, but since this is the latest version according to Microsoft, Mono may someday repeat its delay!