AJAX 101

I started ajaxing about 1 year ago, thats june 08. Since ajax techniques have become more common and accepted, it was time for me to get going with it. There are no shortages of blogs about ajax or conferences or opinions - so you have to set a specific goal regarding what it is you want to do. Let me explain a bit more.

AJAX is not a single piece of technology - its an idea, implemented mainly in javascript that uses a technique of making a request to the database without having to fully reload the page. There are lots of more eloquent explanations with nice pictures to explain this further, but what i am after, as a developer, is to make the user experience better for software that i am designing. A noble goal. If the application has lots of data and state in it, and as a good developer, you want to maintain that state, then reloading the entire page or event (if you use a MVC framework) is alot of extra work.

It is not uncommon in a interface, to request updated data from the DB - where only a small part of the interface needs to update - so, in some instances, its more user centric to update just that smaller part of the interface for the user.

There are always tradeoffs, and when you use an ajax call to update part of the interface, you are really, to the user, disabling the back button. Since you did not reload the page via a new HTTP request, then there is no new page to "load" in the browser memory.

Sometimes the ajax code is not cross browser compatible. For example, IE and FF do not interpret parts of the DOM (document object) the same. The javascript executes the same in any browser, but the way that we communicate with the elements in the html page differ. This was my initial experience using ajax. Working in FF, but not in IE.

More to follow...