| nables you to write interactive applications while | | | | Ajax allows your internet page to respond to a user |
| reducing the amount of data interchanged between | | | | very similarly to the way your local computer |
| the web browser and web server. This results in | | | | desktop environment would. In a well-developed |
| shorter processing times so you can give your user | | | | Ajax-based site, when you click on a page object, it |
| the ultimate web experience. | | | | responds almost immediately. Any changes to the |
| AJAX. Asynchronous JavaScript and XML, if you | | | | page happen there and then, without the page |
| must know what it stands for. Don't let that put you | | | | disappearing and a new one replacing it. The result? A |
| off. Even if it is comprised of technical words and yet | | | | much more pleasant user experience. Once more, |
| another acronym, more importantly, what is it, and | | | | computers are becoming more interactive and |
| why do you need it? | | | | responsive. |
| Why to use Ajax? | | | | The concept can be a bit difficult to grasp initially, so |
| Mainly to build a fast, dynamic website, but also to | | | | here's a simple example from the RealmSurfer |
| save resources. | | | | website to demonstrate the concept: Ajax example: |
| For improving sharing of resources, it is better to use | | | | search page. At first glance this looks like any other |
| the power of all the client computers rather than just | | | | search page. Notice that advanced search link |
| an unique server and network. Ajax allows to | | | | underneath the search box? When you click it, notice |
| perform processing on client computer (in JavaScript) | | | | that you instantly get a whole lot more functionality |
| with data taken from the server. | | | | inserted into the page -- no page refresh. Click the |
| The processing of web page formerly was only | | | | link again and the process reverses itself. |
| server-side, using web services or PHP scripts, before | | | | This is just a very simple example of the benefits of |
| the whole page was sent within the network. | | | | building Ajax functionality into your site. To get a look |
| But Ajax can selectively modify a part of a page | | | | at some really powerful applications, have a look at a |
| displayed by the browser, and update it without the | | | | few popular Ajax-enabled websites: |
| need to reload the whole document with all images, | | | | Flickr -- one of the first sites to popularise the Ajax |
| menus, etc... | | | | phenomenon, it's still one of the best ways to share |
| For example, fields of forms, choices of user, may | | | | pictures with your friends and family online. Yahoo |
| be processed and the result displayed immediately | | | | was quick to realise the potential, and purchased the |
| into the same page. | | | | company a while back. |
| Remember the internet up until recently? Virtually all | | | | Protopage -- create your own customised, interactive |
| web pages were lifeless objects, similar to pages in a | | | | home page. From the moment you land on the site, |
| magazine, with no intelligence. In order to get a | | | | you can move objects around the page as if they |
| response from a website, you would click a link or | | | | are windows on your desktop, and interact with |
| press a submit button, and your computer would | | | | them just as easily. |
| send a message to the computer hosting the site | | | | There are plenty more Ajax-powered sites, and |
| that it needs to send you back the next page. A little | | | | every day a whole lot more become available. What |
| bit like turning to a new colourful but lifeless page in | | | | makes this technology so special? Here are a few |
| your magazine. | | | | good contributers: |
| Sure, there were some really great new technologies | | | | * It uses relatively well established browser |
| that came along to make the internet more | | | | technology -- no plugins are needed, and most |
| interesting. Animated images, Flash animations, small | | | | browsers these days are fully capable of supporting |
| embedded applications, and scripts downloaded with | | | | Ajax-enhanced pages. |
| the page certainly made the pages a lot more | | | | * For the most part pages are still recognisable by |
| interesting. Yet, when compared to the highly | | | | search engines, meaning that unlike technologies like |
| responsive environment of your desktop computer, a | | | | Flash, search engines will still understand what your |
| web page really could not compete. Click anywhere in | | | | page is about. |
| your local pc environment and you get an immediate | | | | * It's economical. Instead of downloading a whole |
| and logical, virtually instantaneous response from the | | | | page when all you want to know is the weather, a |
| object you clicked, without your entire screen | | | | well designed Ajax-based site will only download the |
| flashing blank and reappearing again from scratch. Do | | | | information you need, leaving everything else |
| the same on a web page until recently, and usually at | | | | perfectly intact. |
| best you would have to wait a few seconds for a | | | | * It's fast and responsive. Because much of the |
| completely new page to reappear, a newly turned | | | | programming code that makes an Ajax-based page |
| page in your virtual magazine. | | | | so useful is downloaded onto your local computer, |
| Until Ajax. Technically Ajax is actually not a new | | | | much of your functionality is very fast and |
| technology, but a clever grouping of a few existing | | | | responsive, the same as any locally installed program. |
| technologies. What has made Ajax a workable | | | | * It's non-proprietary technology. Ajax is a |
| solution is that most people have started using | | | | combination of established web standards. You will |
| browsers capable of supporting these technologies, | | | | never have to pay to use it, and neither will the |
| often without even realising that their browser wields | | | | people who program it for you. |
| these dormant superpowers. | | | | |