Technology / Dynamic HTML
Dynamic HTML (DHTML) is a technology that enables the content of web pages to be changed within the browser, allowing richer, more interactive web pages to be created.

In the most common type of web application, a browser makes a request from a server for a web page. If any part of the web page needs to be changed in response to the user's actions, another request has to be made to the server. This process not only takes time, but generally produces a more rudimentary interface.

Internet Explorer (IE) and Netscape both support DHTML in versions 4 and above, but offer very different implementations and capabilities. Whereas Netscape only supports the positioning, visibility and appearance of specific HTML elements, IE provides access to a rich set of properties for every element of the web page. Internet Explorer also allows elements to be re-arranged, added or removed, and includes intrinsic support for multimedia effects and filters.

DHTML applications do not require Java applets or ActiveX controls to run, nor do they require the use of the Java Virtual machine. This means that DHTML web pages require few resources on a client workstation, like conventional HTML applications. DHTML web pages can also be can generated using Active Server Pages, to deliver the advantages of both technologies.

Although DHTML applications do not require the use of compiled components, there is no reason why they can not be combined in a web page. MicroMac have recently developed a Repair and Overhaul system that integrates these technologies to provide an in-situ explosion of a manufacturing job down to the level of hours spent of individual operations. An ActiveX component allows the jobs to be filtered by a wide range of characteristics using a SQL-based query manager.

Related Links
IE users can view a graphing utility that demonstrates the capabilities of DHTML by clicking on the graph icon.

This demo uses Vector Markup Language (VML) to construct an interactive histogram. VML is a feature of Internet Explorer 5, which provides an XML-based exchange, editing, and delivery format for high-quality vector graphics on the Web.