Part of my day job entails analyzing technologies and how they better serve users. But one of the things we seem to forget when promoting Web 2.0 is the flaws it brings with it. Because one of the core technologies of Web 2.0 is AJAX, I've been looking around for a good analysis of it. David Best's Web 2.0: Next Big Thing or Next Big Internet Bubble seems to do the job. AJAX is a core component of Web 2.0, as it introduces an engine that runs on the client side - the Web browser. Certain actions can be carried out in the engine and need no data transfer to the server; thus, they are carred out only on the client's computer and is thus quite fast, comparable to desktop applications. In the HTML-world of Web 1.0, a Web page has to completely reload after a user action, such as clicking on links, or entering data in a form.
Gmail, Google Maps, and Flickr are all AJAX (and therefore Web 2.0) applications. Yet, just because it's got the Web 2.0 label does not necessarily mean it is "better." Why? Let's take a look at Gmail and Flickr, and see the advantages and disadvantages of their reliance on AJAX-technology:
(1) Rich User Experience - Fasst! Response to user actions are quick and the Web applications behave like desktop applications (e.g. drag and drop).
(3) The Back Button - Because Web browsers usually keep a history of whole Web pages in Web 1.0, many are often surprised that Gmail does not allow this as it is an AJAX application, for single actions are not cacheable for the browser.
(4) Bookmarking - Web 2.0 is based on rich user experience; unfortunately, this means that as with many dynamically generated pages, bookmarking or linking to a certain state of such a page is nearly impossible, as those states are not uniquely identifiable by URL. (Try bookmarking on Flickr!)