Dynamic HTML, or DHTML, is a collection of technologies used together to create interactive and animated web sites by using a combination of a static markup language (such as HTML), a client-side scripting language (such as JavaScript), a presentation definition language (such as CSS), and the Document Object Model. HTML, an initialism of HyperText Markup Language, is the predominant Markup language for Web pages It provides a means to describe the structure HTML has been in use since 1991, but HTML 40 (December 1997 was the first standardized version where international characters were given reasonably complete treatment In HTML and XHTML, a font face or font family is the typeface that is applied to some text An HTML editor is a software application for creating Web pages Although the HTML markup of a web page can be written with any Text editor, specialized In Computing, an HTML element indicates structure in an HTML document and a way of hierarchically arranging content HTML Series The W3C HTML standard includes support for Client-side scripting. A layout engine, or rendering engine, is software that takes marked up content (such as HTML, XML, image files etc Quirks mode refers to a technique used by some Web browsers for the sake of maintaining backwards compatibility with Web pages designed for older browsers instead of Web style sheets are a form of Separation of presentation and content for Web design in which the markup (i Web pages authored using hypertext markup language ( HTML) may contain multilingual text represented with the Unicode universal character set. Web colors are Colors used in designing web pages and the methods for describing and specifying those colors The Extensible Hypertext Markup Language, or XHTML, is a The following tables compare general and technical information for a number of Web browsers Please see the individual products' articles for further information The following tables compare HTML compatibility and support for a number of Layout engines Please see the individual products' articles for further information The following tables compare support of HTML 5 differences from HTML 4 for a number of Layout engines The specification is still a working draft not The following tables compare deprecated and proprietary HTML tags and attributes compatibility and support for a number of Layout engines Please see the individual products' articles for The following tables compare XHTML compatibility and support for a number of Layout engines Please see the individual products' articles for further information A website (alternatively web site or Web site, a back-construction from the Proper noun World Wide Web) is a collection of Web pages A markup language is an Artificial language using a set of annotations to text that give instructions regarding the structure of text or how it is to be displayed HTML, an initialism of HyperText Markup Language, is the predominant Markup language for Web pages It provides a means to describe the structure Client-side scripting generally refers to the class of Computer programs on the web that are executed Client-side, by the user's JavaScript is a Scripting language most often used for Client-side web development The Document Object Model ( DOM) is a platform- and language -independent standard Object model for representing HTML or XML and related

A DHTML webpage is any webpage in which client-side scripting changes variables of the presentation definition language, which in turn affects the look and function of otherwise "static" HTML page content, after the page has been fully loaded and during the viewing process. Thus the dynamic characteristic of DHTML is the way it functions while a page is viewed, not in its ability to generate a unique page with each page load.

By contrast, a dynamic web page is a broader concept — any web page generated differently for each user, load occurrence, or specific variable values. Classical Hypertext navigation occurs among This includes pages created by client side scripting, and ones created by server-side scripting (such as PHP or Perl) where the web server generates content before sending it to the client. Server-side scripting is a Web server technology in which a user's request is fulfilled by running a script directly on the web server to generate dynamic HTML pages PHP is a computer Scripting language. Originally designed for producing Dynamic web pages it has evolved to include a Command line interface capability NOTES FOR EDITORS "Perl" is not an acronym (read the "Name" section below

Uses

DHTML is often used to make rollover buttons or drop-down menus on a web page.

A less common use is to create browser based action games. During the late 1990s and early 2000s, a number of games were created using DHTML, but differences between browsers made this difficult: Many techniques had to be implemented in code to enable the games to work on multiple platforms. Recently browsers have been converging towards the web standards, which has made the design of DHTML games more viable. Those games can be played on all major browsers and they can also be ported to Widgets for Mac OS X and Gadgets for Windows Vista, which are based on DHTML code. Mac OS X (mæk oʊ ɛs tɛn is a line of computer Operating systems developed marketed and sold by Apple Inc, the latest of which is pre-loaded on all currently Windows Vista (ˈvɪstə is a line of Operating systems developed by Microsoft for use on Personal computers including home and business desktops

The term has fallen out of use in recent years, as DHTML scripts often tended to not work well between various web browsers. Newer techniques, such as unobtrusive JavaScript coding (DOM Scripting), allow similar effects, but in an accessible, standards-compliant way through Progressive Enhancement. The term DOM Scripting refers to programmatically accessing the Document Object Model (DOM Progressive enhancement is a strategy for Web design that emphasizes accessibility semantic markup and external stylesheet and scripting technologies

Some disadvantages of DHTML are that it is difficult to develop and debug due to varying degrees of support among web browsers of the technologies involved, and that the variety of screen sizes means the end look can only be fine-tuned on a limited number of browser and screen-size combinations. Development for relatively recent browsers, such as Internet Explorer 5.0+, Mozilla Firefox 2. Microsoft Internet Explorer 5 (abbreviated IE5) is a graphical Web browser released in March 1999 by Microsoft, primarily for Microsoft Windows 0+, and Opera 7. Opera is a Web browser and Internet suite developed by the Opera Software company 0+, is aided by a shared Document Object Model. Basic DHTML support was introduced with Internet Explorer 4.0, although there was a basic dynamic system with Netscape Navigator 4.0. Microsoft Internet Explorer 4 (also IE4) is a graphical web browser released in September 1997 by Microsoft, primarily for Microsoft Windows, but also Netscape Navigator and Netscape are the names for the proprietary Web browser popular in the 1990s and the Flagship product of the Netscape

Structure of a web page

See also: DOM events

Typically a web page using DHTML is set up the following way:

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1. DOM events allow Event-driven programming languages like JavaScript, JScript, ECMAScript, VBScript and Java to register 1//EN" "http://www. w3. org/TR/xhtml11/DTD/xhtml11. dtd">
<html xmlns="http://www. w3. org/1999/xhtml">
  <head>
    <title>DHTML example</title>
    <script type="text/javascript"> 
      function init() {
      myObj = document. getElementById("navigation");
      // . . . .  more code]]
      }
      window. onload=init;
    </script>
  </head>
  <body>
    <div id="navigation"></div>
    <pre>
      Often the code is stored in an external file; this is done by linking the file that contains the JavaScript.  
      This is helpful when several pages use the same script:
    </pre>
    <script type="text/javascript" src="myjavascript. js"></script>
  </body>
</html>

In the above code, the blue code represents the DOCUMENT TYPE declaration, which specifies which version of markup code is used to create the website. The red code shows browser detection Javascript, which enables web pages to adjust to browser application standards and requirements.

Example: displaying an additional block of text

The following code illustrates an often-used function. An additional part of a web page will only be displayed if the user requests it. In e-learning, such a function could be used to display additional hints or an answer the student initially should not see. Electronic learning (or e-Learning or eLearning) is a type of education where the medium of instruction is computer technology

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1. 0 Strict//EN" 
      "http://www. w3. org/TR/xhtml1/DTD/xhtml1-strict. dtd">
<html xmlns="http://www. w3. org/1999/xhtml" xml:lang="en">
  <head>
    <title>Test</title>
    <style type="text/css">
      h2 {background-color: lightblue; width: 100%}
      a {font-size: larger; background-color: goldenrod} 
      a:hover {background-color: gold}
      #example1 {display: none; margin: 3%; padding: 4%; background-color: limegreen}
    </style>
    <script type="text/javascript">
      function changeDisplayState (id) {
        d=document. getElementById("showhide");
        e=document. getElementById(id);
        if (e. style. display == 'none' || e. style. display == "") {
          e. style. display = 'block';
          d. innerHTML = 'Hide example. . . . . . . . . . . . . . ';
        } else {
          e. style. display = 'none';
          d. innerHTML = 'Show example';
        }
      }
    </script>
  </head>
  <body>
    <h2>How to use a DOM function</h2>
    <div><a id="showhide" href="javascript:changeDisplayState('example1')">Show example</a></div>
    <div id="example1">
      This is the example. 
      (Additional information, which is only displayed on request). . . 
    </div>
    <div>The general text continues. . . </div>
  </body>
</html>

External links

• QuirksMode, a comprehensive site with test examples and instructions on how to write DHTML code which runs on several browsers.
• Introductory DHTML Tutorial for those taking their first steps in DHTML.
• HTML & DHTML Reference on MSDN