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.

The Flex SDK comes with a set of user interface components including buttons, list boxes, trees, data grids, several text controls, and various layout containers. Charts and graphs are available as an add-on. Other features like web services, drag and drop, modal dialogs, animation effects, application states, form validation, and other interactions round out the application framework.

In a multitiered model, Flex applications serve as the presentation tier. Unlike page-based HTML applications, Flex applications provide a stateful client where significant changes to the view don’t require loading a new page. Similarly, Flex and Flash Player provide many useful ways to send and load data to and from server-side components without requiring the client to reload the view. Though this functionality offered advantages over HTML and JavaScript development in the past, the increased support for XMLHttpRequest in major browsers has made asynchronous data loading a common practice in HTML-based development as well.

In countries all around the world, people follow the sources most relevant to them and access information via Twitter as it happens—from breaking world news to updates from friends.

Dorsey grew up in st.louis mussouri. By age 14, he was interested in dispatch routing. Some of his open source software in this genre is still in use by taxicab companies. While working on dispatching as a programmer he later moved to california.

In Oakland in 2000, Dorsey started his company to dispatch couriers, taxis, and emergency services from the Web. His other projects and ideas at this time included networks of medical devices and a “frictionless service market”. In July 2000, building on dispatching and inspired in part by Live journal and possibly by AOL instant manager, he had the idea for the realtime status communication.

When he first saw implementations of instant messaging, Dorsey had wondered if the software’s user status output could be shared among friends easily. He approached Odea, who at the time happened to be interested in text messaging Dorsey and biz stone decided that SMS text suited the status message idea, and built a prototype of Twitter in about two weeks.The idea attracted many users at Odeo and investment from Evan williams who had left google after selling them pyra labs and blogger.