Flex is the next step in the development of RIAs. The phrase rich Internet applications was coined by Macromedia (now Adobe) in 2002 to account for the trend in more expressive applications on the web. In the beginning, HTML documents on the web were just that, documents. They were text and, later, images and multimedia. This client-server paradigm meant a user, by typing a URL in their browser, would request a document. The web being so far-reaching, savvy folks quickly learned to create server-based applications, programs, which a user could access online. Think of all those forms you’ve filled out, where you type your name and address and hit the submit button. After a few moments, you’re greeted with an entirely new page telling you your form was submitted (or that you had some errors you have to fix first). This was a client-server model, where a “thin” client (a browser) requested content and sent it back to a server for processing. To create dynamic HTML pages, a server had to create the HTML and send it to the client, which would read it like any other page. This took time. Then, with the advent of JavaScript came the power to offload some application workload onto the client. For instance, when configuring an item in an online store, it used to be necessary send all calculations like shipping or sales tax back to the server. With scripting, it was possible to calculate that information right on the client machine and update the layout of the page based on user interaction. Dubbed a “thick” client in contrast to the thin client, a user’s computer needed to be a bit more powerful in order to run the scripts and re-render the page.