ADOBE FLEX ...the simplest way of web designing

Adobe Flex is a software development kit released by Adobe Systems for the development and deployment of cross-platform rich Internet applications based on the Adobe Flash platform. Flex applications can be written using Adobe Flex Builder or by using the freely available Flex compiler from Adobe.
The initial release in March 2004 by Macromedia included a software development kit, an IDE, and a J2EE integration application known as Flex Data Services. Since Adobe acquired Macromedia in 2005, subsequent releases of Flex no longer require a license for Flex Data Services, which has become a separate product rebranded as LiveCycle Data Services.
In February 2008, Adobe released the Flex 3 SDK under the open source Mozilla Public License. Adobe Flash Player, the runtime on which Flex applications are viewed, and Adobe Flex Builder, the IDE built on the open source Eclipse platform and used to build Flex applications, remain proprietary.

Traditional application programmers found it challenging to adapt to the animation metaphor upon which the Flash Platform was originally designed. Flex seeks to minimize this problem by providing a workflow and programming model that is familiar to these developers. MXML, an XML-based markup language, offers a way to build and lay out graphic user interfaces. Interactivity is achieved through the use of ActionScript, the core language of Flash Player that is based on the ECMAScript standard.

[edit] Release history
Flex 1.0 - March 2004
Flex 1.5 - October 2004
Flex 2.0 (Alpha) - October 2005
Flex 2.0 Beta 1 - February 2006
Flex 2.0 Beta 2 - March 2006
Flex 2.0 Beta 3 - May 2006
Flex 2.0 Final- June 28, 2006
Flex 2.0.1 - January 5, 2007
Flex 3.0 Beta 1 - June 11, 2007
Flex 3.0 Beta 2 - October 1, 2007
Flex 3.0 Beta 3 - December 12, 2007
Flex 3.0 - February 25, 2008
Flex 3.1 - August 15, 2008
Flex 3.2 - November 17, 2008
Flex 3.3 - March 4, 2009