Macromedia introduced Flex in 2004 so that developers could write web applications for the nearly ubiquitous Flash platform. These applications benefited from the improved design, usability, and portability that Flex made possible, dramatically changing the user experience. These features are a cornerstone of Web 2.0, a new generation of Internet applications focused on creativity and collaboration.

Since the introduction of Flex, Macromedia—and now Adobe—has released versions 1.5, 2, 3, 4, and 4.5 of Flex. With each subsequent version, creating rich, compelling, intuitive applications has gotten easier, and the bar has been raised on users’ expectations of web applications. Countless organizations have discovered the benefits of Flex and have built and deployed applications that run on the Flash platform.

But Flex 1 and 1.5 were most definitely not mass-market products. The pricing, lack of IDE, limited deployment options, and other factors meant that those early versions of Flex were targeted specifically for large and complex applications as well as for sophisticated developers and development. However, with the new releases of the Flex product line, all this has changed.

Flex 2 was released in 2006 and made Flex development a possibility for many more people, as it included a free software development kit (SDK). With the open sourcing of Flex 3, and the announcement of free versions of Flash Builder for students, Flex development is within the grasp of any developer with enough foresight to reach for it. The release of Flex 4 made it even easier to build rich, efficient, cutting-edge applications, and streamlined the workflow between designer and developer, greatly easing the process of bringing intuitive, compelling designs to even more Flex applications. In this latest release, Flex 4.5, Adobe has further extended the reach of Flex, making it possible to deploy applications not only to browsers and desktops, but to phones, tablets, televisions, and other connected devices.

Getting started with Flex is easy. Flex itself is composed of two languages: MXML, an XMLbased markup language, and ActionScript, the language of Flash Player. MXML tags are easy to learn (especially when Flash Builder writes them for you). ActionScript has a steeper learning curve, but developers with prior programming and scripting experience will pick it up easily. Still, there’s more to Flex development than MXML and ActionScript.