Adobe Flex SDK

Flex SDK will provide a highly productive, open source framework for building and maintaining expressive web applications that deploy consistently on all major browsers, desktops and operating systems.
It provides a modern, standards-based language and programming model that supports common design patterns suitable for developers from many backgrounds. Flex applications run in the ubiquitous Adobe Flash Player and Adobe AIR.
You can use the Flex SDK to create a wide range of highly interactive, expressive applications. For example, a data visualization application built in Flex can pull data from multiple back-end sources and display it visually. Business users can drill down into the data for deeper insight and even change the data and have it automatically updated on the back end.
A product configuration application can help customers navigate the process of selecting or customizing products online. And a self-service application can guide customers through an address change or help employees complete an otherwise complicated multi-step benefits enrollment.
In addition to the Open Source Flex SDK, Adobe produces the Free Adobe Flex SDK which contains everything in the Open Source Flex SDK plus useful tools for enhancing the application development experience such as the debugger Adobe Flash Player runtime and Adobe AIR. Adobe also provides a professional IDE, Adobe Flex Builder, for building Flex applications using either the Adobe Flex SDK or the Open Source Flex SDK.