This document introduces JavaScript and discusses its most fundamental concepts. It is meant to help you better understand the rest of the tutorials.
JavaScript is a scripting language originally developed by Netscape® Communications for use in their World Wide Web browsers.
A script is a type of computer code, or a set of instructions that can directly be executed by a program that understands the language in which the script is written. JavaScript code is inserted directly into the HTML page.
Core JavaScript was initially used to augment the processing of HTML forms, and included the basic functions needed for computing and validating user inputs.
The later introduction of the W3C specfication for the Document Object Model, or DOM, greatly expanded the possible uses of the language. The DOM defines the way in which an HTML document's elements are exposed as objects to scripts. JavaScript used in conjunction with the DOM provide the foundation for Dynamic HTML.