Web 1.0 to Web 2.0/AJAX

• Web 1.0: At the beginning of the Web content and “application” era, browsers were designed to support lightweight scripting on the client side, and many user interface behaviors had to be done on the server side, which required round trips and heavy server state management.
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• Web 2.0/AJAX: With the avenue of AJAX, which allows an application to request more content without refreshing the page, application developers had the ability to put more logic on the client side to start building a "desktop-like" experience in a browser.

Understanding HTML5 for Applications

understanding HTML5 for applications is understanding that HTML5 is HTML, that HTML5 is a living specification, and that, thanks to the momentum and ecosystem behind HTML5, HTML has become the only fully cross-device (and cross-distribution) environment allowing developers to build rich applications for PC, mobile devices, and tablets and distribute them via the Web or application stores. Best of all, we are just at the beginning!

In other words,

HTML5 = (HTML4 + 1) + (CSS2 + 1) + SVG = Rich Experience + Cross Platform + Web + App Store

• First, data exists 1 in databases, file systems, or even Web services.
• Upon a specific request, data logic 2 extracts and organizes the data needed to serve the request into a      data model 3 to be rendered to the user.
• Then, the model 3 is combined with a template 4 (e.g., JSP, Freemarker, PHP, Mustache, or JsRender) to generate the HTML 3 that the browser will ultimately display to the user.
• Before and/or after the content is displayed, behavior logic 6 is "attached" to the HTML document.
• Upon user interaction 7, the behavior logic 6 handles the interaction by eventually updating all or part of the application by restarting the flow entirely or partially.