Web Design

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n the early days of the Web, a need arose to allow designers to provide some sort of interactivity

for their users. Netscape, at the time the developer of the most popular browser, created a

lightweight scripting language for that purpose. Named JavaScript, it was first introduced with

the Netscape 2 browser in 1996. Although attempts were made to create competing languages,

eventually every browser manufacturer adopted JavaScript in its browsers. The European Computer

Manufacturers Association maintains a standardized version, known more formally as ECMAScript.

Introduction to JavaScript and Ajax

Writing JavaScript

JavaScript is text-based, and can be written in any text editor. Almost

all editors designed for writing Web pages, whether they are code-

based or visual editors, likely provide help in the form of code hints

and syntax highlighting for JavaScript. function hideDiv(){

document.getElementById("specials").style.visibility = "hidden";}function showDiv()

{ document.getElementById("specials").style.visibility = "visible";}

function hideDiv(){

document.getElementById("specials").style.visibility = "hidden";}

function showDiv(){

document.getElementById("specials").style.visibility = "visible";}

Browser Support

Every major modern browser offers full support of JavaScript.

Microsoft’s Internet Explorer officially supports ECMAScript, but

this in effect means support of JavaScript. You can safely

assume that, unless your user has specifically disabled it, all

browsers will run your scripts.

Running JavaScript

In order to run, your JavaScript code must be

interpreted by an application. In most cases, the

application being used to run it will be a Web

browser. However, many other applications support

JavaScript in some form today, so you might also

encounter it being used elsewhere.

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