Syscon Softech Blog

JAVASCRIPT

Introduction

Netscape originally invented a simple scripting language called LiveScript, which was to be a proprietary add-on to HTML. When Sun’s new language Java became unexpectedly popular, Netscape was quick to jump on the Java bandwagon, and re-christened their scripting language JavaScript. Outside of the first four letters, there are almost no other similarities between the two.

Microsoft then added their own version of JavaScript to Internet Explorer, which they named JScript. Unfortunately, the two were not identical, so Netscape then attempted to straighten matters out by turning JavaScript over to ECMA, a Switzerland-based standards body. This gave three main versions of JavaScript-based languages: JavaScript, which works primarily with Netscape’s browsers, JScript, which works with Internet Explorer, and ECMAScript, with which no browser is completely compatible. Netscape and Microsoft have both stated that future versions will match the ECMAScript standard, which should lead to convergence. However, as the most-used features are common to all, compatibility is not an issue unless you are trying to use JavaScript to control DHTML.

What is JavaScript?

* JavaScript is a scripting

* A scripting language is a lightweight programming language.

* Language JavaScript was designed to add interactivity to HTML pages.

* JavaScript is usually embedded directly into HTML pages.

* JavaScript is an interpreted language (means that scripts execute without preliminary compilation).

* Everyone can use JavaScript without purchasing a license.

* JavaScript is a compact, object-based scripting language for Web pages.

* JavaScript code embedded into your HTML pages can enhance them with many interesting elements, from

swapping images when you move a cursor over them, to multi-level drop-down menus.

* You can create really sophisticated and almost application-like pages with the help of JavaScript. You don’t need

any special software other than a text editor and a Web browser, and you don’t need access to a Web server.

Here are a few examples of what you can do with JS:-

Change the look of the page, colors, fonts, switch images, etc. Validate and calculate forms, Animate things,Adjust the page to fit the user’s browser, resolution, platform, etc.

JavaScript is growing in popularity due to its simple learning curve relative to the amount of power it provides. Complete non-programmers are able to add a little bit of interactivity to their web pages without buying an IDE or sweating over why a program won’t compile. There are numerous Web sites which contain any number of scripts available for the taking, and Netscape has fairly complete documentation on their site. And of course, there’s the always useful ability to view the source of Web pages.

Are Java and JavaScript the Same?

NO!Java and JavaScript are two completely different languages in both concept and design!

Java (developed by Sun Microsystems) is a powerful and much more complex programming language - in the same category as C and C++.Although the names are almost the same, JavaScript isn’t the same as Java. These are two different techniques for Internet programming. Java is a real programming language, and you can create real programs with it.JavaScript is a scripting language. You could even say that JavaScript is rather an extension to HTML than a separate computer language. It’s so tightly integrated with HTML that you could call it “JavaScript markup language.” JavaScript coders don’t care too much about real programming, they just make different nice effects by inserting small JavaScript code fragments into their Web pages.