"One of the most appealing things about Flex is that Flash was created with the idea of UI first. In a very real sense, it’s a domain-specific language (DSL) for graphics, multimedia, and UIs, whereas most other solutions have been languages with UI libraries tacked on afterwards.
Because of this design goal, Flex and Flash provide a complete, unlimited, flexible tool to build user experiences. From the standpoint of a programmer’s time investment, you can learn a single language for building UIs without worrying about running into problems or limitations later—issues like:
- Installation problems
- Constraints on what you can create
- Sudden steep climbs in the learning curve