Web-based communities

        Some web-sites that potentially sit under the Web 2.0 umbrella have built new online social networks amongst the general public. Some of these sites run social software where people work together. Other sites reproduce several individuals' RSS feeds on one page. Other ones provide deeplinking between individual web-sites.

        The syndication and messaging capabilities of Web 2.0 have fostered, to a greater or lesser degree, a tightly-woven social fabric among individuals. Arguably, the nature of online communities has changed in recent months and years. The meaning of these inferred changes, however, has pundits divided. Basically, ideological lines run thusly: Web 2.0 either empowers the individual and provides an outlet for the "voice of the voiceless"; or it elevates the amateur to the detriment of professionalism, expertise and clarity.

 

Web-based applications and desktops

        The richer user-experience afforded by Ajax has prompted the development of web-sites that mimic personal computer applications, such as word processing, the spreadsheet, and slide-show presentation. WYSIWYG wiki sites replicate many features of PC authoring applications. Still other sites perform collaboration and project management functions. Java enables sites that provide computation-intensive video capability. Google, Inc. acquired one of the best-known sites of this broad class, Google Docs & Spreadsheets, in early 2006.

        Several browser-based "operating systems" or "online desktops" have also appeared. They essentially function as application platforms, not as operating systems per se. These services mimic the user experience of desktop operating-systems, offering features and applications similar to a PC environment. They have as their distinguishing characteristic the ability to run within any modern browser.

        Numerous web-based application services appeared during the dot.com bubble of 1997–2001 and then vanished, having failed to gain a critical mass of customers. In 2005 WebEx acquired one of the better-known of these, Intranets.com, for slightly more than the total it had raised in venture capital after six years of trading.

 

Rich Internet applications

        Recently, rich-Internet application techniques such as Ajax, Adobe Flash, Flex and OpenLaszlo have evolved that can improve the user-experience in browser-based applications. Flash/Flex involves a web-page requesting an update for some part of its content, and altering that part in the browser, without refreshing the whole page at the same time.

 

Server-side software

        The functionality of Web 2.0 rich Internet applications builds on the existing Web server architecture, but puts much greater emphasis on back-end software. Syndication differs only nominally from the methods of publishing using dynamic content management, but web services typically require much more robust database and workflow support, and become very similar to the traditional intranet functionality of an application server. Vendor approaches to date fall under either a universal server approach, which bundles most of the necessary functionality in a single server platform, or a web-server plugin approach, which uses standard publishing tools enhanced with API interfaces and other tools..