ARCHIVED: What is JavaScript?

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JavaScript is an object-oriented scripting language developed by Netscape Communications for client/server applications. JavaScript is not the same as Java, although the languages do have similar syntax.

There are two types of JavaScript:

Navigator (client-side) JavaScript
LiveWire (server-side) JavaScript

Navigator JavaScript

All versions of Netscape Navigator starting with version 2.0 are capable of interpreting JavaScript statements that are part of an HTML document. When a remote site sends a document containing JavaScript statements, your browser executes these statements, producing the results you see.

LiveWire JavaScript

LiveWire refers to a development environment for creating server-based applications using JavaScript. These applications are similar to CGI scripts in their behavior.

Basic differences between JavaScript and Java

JavaScript is an interpreted language, while Java code is compiled before you download it.
JavaScript does not support classes or inheritance.
JavaScript has "loose typing"; that is, you don't need to specify the data types of variables.
More browsers support Java than JavaScript.

This document is loosely based on information obtained from Netscape's JavaScript Guide:

  http://wp.netscape.com/eng/mozilla/3.0/handbook/javascript/