Open CSS

JavaScript is an object-oriented scripting language originally developed by Netscape Communications under the name LiveScript but then renamed to "JavaScript" and given a syntax closer to that of Sun Microsystems' Java language. JavaScript was later standardized by ECMA under the name ECMAScript. The current standard (as of December 1999) is ECMA-262 Edition 3, and corresponds to JavaScript 1.5. Microsoft calls their version JScript.

Java and JavaScript
The change of name from LiveScript to JavaScript happened at roughly the same time Netscape was including support for Java technology in its Netscape Navigator browser. Consequently, the change proved a source of much confusion. There is no real relation between Java and JavaScript; their only similarities are some syntax and the fact that both languages are used extensively on the World Wide Web.

Usage
JavaScript is an object-oriented scripting language that connects through interfaces called Document Object Models (DOMs) to applications, especially to the server side (web servers) and the client side Web browser of internet applications. Many web sites use client-side JavaScript technology to create powerful dynamic web applications. It may use Unicode and can evaluate regular expressions (introduced in version 1.2 in Netscape Navigator 4 and Internet Explorer 4). JavaScript expressions contained in a string can be evaluated using the eval function.

One major use of JavaScript is to write little functions that are embedded in HTML pages and interact with the DOM of the browser to perform certain tasks not possible in static HTML alone, such as opening a new window, checking input values, changing images as the mouse cursor moves over etc. Unfortunately, the DOMs of browsers are not standardized, different browsers expose different objects or methods to the script, and it is therefore often necessary to write different variants of a JavaScript function for the various browsers.

JavaScript/ECMAScript is implemented by:

-KJS
-Rhino
-Spider Monkey
-NJS
-NGS

JavaScript and JScript contain several properties which are not part of the official ECMAScript standard, and also miss several properties. As such, they are in points incompatible, which requires script authors to work around these bugs.
This also means every browser may treat the same script differently, and what works for one browser may fail in another browser, or even in a different version of the same browser. Like with HTML, it is thus advisable to write standards-compliant code.

JavaScript is a small, lightweight, object-oriented, cross-platform scripting language.JavaScript is the Netscape-developed object scripting language used in millions of web pages and server applications worldwide.

JavaScript is text-based. JavaScript is a scripting language. The main use of JavaScript is to provide a level of interactivity to web pages that are not achievable with simple HTML.

JavaScript is an implementation of the ECMAScript language standard and is typically used to enable programmatic access to computational objects within a host environment. It can be characterized as a prototype-based object-oriented.

JavaScript is source is an excellent JavaScript resource. It is a small, lightweight, object-oriented, cross-platform scripting language and it reference includes complete documentation for JavaScript 1.5 and updates.