Browser technologies have experienced an enormous amount of growth since the very beginning, from the simple static pages of HTML down to the full blown animation and interaction of flash. The number of tools available to webpage development have exploded and you are no longer limited to a few options in building your page.
In more recent years, basic HTML pages have become a little bit more boring, so developers were really scrambling to make their sites a little bit more interesting to the viewers. One aspect that was looked into was how to make pages a little bit more interactive to give it more flavor. Although there were many standards that were created, we will discuss two here for brevity’s sake.
Boring HTML pages gave way to the rise of DHTML or Dynamic HTML. DHTML allows the webpage creator to program specific responses to exact actions that the viewer does. This is very apparent when a viewer moves his mouse on top of a button and the button glows or looks pressed. This is a capability of DHTML that is not possible with HTML alone.
Another aspect of HTML that people wanted to change was its behavior whenever you request to change something. HTML always reloads the page so that it can show the newly requested page. They found a solution called IFrame to this that allowed the user to reload a frame at a time if he wanted to; but this was found to be quite lacking. AJAX or Asynchronous Javascript and XML was created to remedy this specific shortcoming of HTML. AJAX allows the pages to request only the data that it needs to change and not the whole page. This can be clearly seen in webpages that show you a gallery of pictures. Before AJAX, when you click next, the whole page reloads to show the next picture. But with AJAX, only that picture changes and the rest of the page doesn’t even move.
In essence, AJAX and DHTML are two of the remedies that were created to augment the capabilities of HTML. DHTML does this by changing the elements on the screen depending on what the user’s actions are. While AJAX allows the browser to request certain elements at a time to reduce the strain on the internet connection and avoid the annoying reloading process. With that in mind, we can say that AJAX and DHTML, used at the same time could greatly improved a users viewing experience.
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