Find Web Developers
Find Web Developers

AJAX – The Incredible Breakthrough in Web 2.0

In the ’90s, when “Dynamic web” technology that allows programmers to quickly develop Web-based applications with interaction with users, many have ever hoped that one day all the applications we use would be web-based instead of software running independently on a single computer (desktop-based application). Indeed, together with the rapid growth of the Internet and the huge advantages of Web applications (accessible, available everywhere, every when without having to upgrade much of the used machinery…), the future of software firm will certainly be closely associated with Web applications, or be replaced in other words. However, until now, the hope has not been thoroughly met because a number of features of Web applications is the limit that seems to be impossible to pass. That is the way in which Web users and applications interact with each other.

Different from stand-alone applications running in client, web ones are limited by its operation theory: communicate through HTTP protocol in the client-server methodology. Any action from user to web will have the browser to fetch data to server. Therefore, delay is the most essential drawback of web applications.

On one beautiful day in the spring of 2005, there went a term which created an incredible throughout and changed the whole dot-com world since 2005: The invention of AJAX. Web 2.0 generation has just started and will have to undergo a long road ahead to be able to change what’s already become familiar to people today. It is the complex web of AJAX technology which plays a key role in the second phase. The world has not really ready to receive, many people think that AJAX applications are developing faster than Moore’s law – driving force through the computing origins.

What is AJAX?

AJAX (shorthand for Asynchronous JavaScript and XML) is a set of tool for optimizing high speed of web applications by retrieve small pieces of data from the server asynchronously in the background without interfering with the display and behavior of the existing page, rather than loading the whole page. AJAX is not a single technology; it is the combination of interrelated web development techniques. In particular, HTML and CSS display data, DOM model presents XMLhttpRequest object information. Despite the name, the use of XML is not actually required nor do the requests need to be asynchronously.

Most of stories about the origins of AJAX begin since the moment Microsoft developed Remote Scripting technology in 1998. However, the method of asynchronous content transferring had appeared in the element IFRAME of Internet Explorer 3 (1996) and LAYER of Netscape 4.0 (1997). On introducing IE 4.0, Microsoft use the object-oriented model different DOM. By 2000, Netscape completely lost his browser market before Bill Gate’s vendor and element LAYER went to history.

Several years later in 2005, the appearance of brand-new AJAX just drew the attention of the cyber civilization and became the GUI improvement tools for web applications. Since then, AJAX has become the center of every stories and topic related to web 2.0 generation.

How does AJAX work?

Computer users always dream of one day when desktop-base software will be stored and run completely from web instead of from their limited-space hard drives. However, the dream comes false. They forget that Web applications are restricted by the principle in which all actions must be done through HTTP (Hyper Text Transfer Protocol – protocol transmission via hyperlinks). Activities from user on the sites will generate an HTTP request to servers. Servers perform some processing stage like retrieving data, calculating and examining the validity of information, modifying memory, then send a complete HTML page to the client. Technically, this method seems to be reasonable but quite inconvenient and time consuming in fact as what will users do while servers are busy doing its role. We have to WAIT.

To overcome the above problem, developers introduced intermediate method: AJAX processing – between client and server. This is like adding a layer between processes to reduce the time of “information walking” and responding time. Instead of reloading (refresh) the entire page, it only loads a section of the page which changed while other parts remain. Then when browsing a page that supports AJAX, users will never see a white window (blank) and hourglass icons – symbol indicating that server is performing its task. For example, in a photo website, with traditional applications, the entire page containing the photo website will be open form the beginning and the all of images will be load again if there is any change. When applying AJAX, DHTML just replace the title and just editing, which make transactions smooth and fast.

All actions of the user send JavaScript command to the AJAX processor instead of creating an HTTP request (HTTP request) and queries to servers. If you need anything from the server, download additional code, such as updating interface code or receiving new data, AJAX request will be transmitted to a server asynchronously, usually by using XML, without disrupting the interaction of users.

Common AJAX applications

Google Suggest display suggested terms almost immediately even when user has not finished typing your keywords. Now with Google Maps, people can track the change, move, drag the map as desktop environments. Google Suggest and Google Maps are two examples which highlight the methods of new-generation Web applications. The world’s leading search service vendor has invested heavily in the development of AJAX.. Almost all the programs they introduced recently, from Orkut, Gmail beta to Google Groups, are all AJAX applications.

Many other companies are following this trend as photo-sharing site Flickr, or the Amazon’s A9.com search engine. Yahoo vendor has released a new Yahoo Mail Beta uses Ajax technology. New mail boxes will be retrofitted under Web 2.0 like RSS feeds, preview… Microsoft is also implementing the program Windows Live Mail and Windows Live Messenger which support AJAX.

Those projects showed that AJAX is not a too distant technology that is presented in the real world, from very simple models such as Google Suggest to the sophisticated and complex as Google Maps.

The biggest challenges in creating Ajax applications are not technical. The core Ajax technologies are mature, stable, and well understood. Instead, the challenges are for the designers of these applications: to forget what we think we know about the limitations of the Web, and begin to imagine a wider, richer range of possibilities..” (Alexei White, Production Director of eBusiness Company commented. “AJAX will gradually affect Microsoft’s loss in the market. Although it can not be completely overwhelmed, it will bring alternative features for the most part as the Office product.”

The Drawback

AJAX can contribute to create a new generation of web applications. However, it is also a dangerous technology to cause many troubles in the user interface. For example, we press “Back” (back to previous page) was rated in the standard Web interface. Unfortunately, this function does not work with Javascript and people cannot find the previous content by pressing Back. Therefore, only a small preliminary data on the site is altered and can not be recovered. This is one of the main reasons that many applications do not support Javascript.

Besides, people can not save the web address as their Favorite or Bookmark to review later. Applied by the mediated class for transaction, AJAX applications do not have a fixed address for each item. This shortcoming makes AJAX easy to lose it points in user’s eyes.

The browser support AJAX is Microsoft Internet Explorer 5.0 or higher, based on Gecko browsers like Mozilla, SeaMonkey and Netscape 7.1; contains KHTML like Konqueror API 3.2 or higher, Safari and so on…

Comments are closed.