The Microsoft Silverlight Release History containing information on each public release of Silverlight. Available through the Microsoft Download Center the Silverlight Release History is a .htm file which enumerates all the major versions of the technology.
Silverlight 1 Build 1.0.20816.00 was released on September 4, 2007, and at that time observers commented on Microsoft’s definite move against Adobe’s Flash.
Fast forward four years later Microsoft has embraced HTM5 with IE9, while Adobe Flash is very much still alive also.
Silverlight 2 Build 2.0.31005.00 was launched on October 14, 2008 and it was followed in less than a year by Silverlight 3 Build 3.0.40624.00 on July 9, 2009.
Yet again in less than 12 months Silverlight 4 Build 4.0.50401.00 hit the web on April 15, 2010, and is the version to get most updates to date.
With the advent of Internet Explorer 9 things changes a tad on the HTML5 support front, and now the Redmond company received critics for an apparent move to kill Silverlight with IE9. Yes, it’s amazing how things change in just a few years.
Silverlight 5 is right on track for being finalized by the end of 2011.
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