JavaScript/History of JavaScript

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JavaScript was originally developed by Brendan Eich of Netscape Communications Corporation under the name Mocha, then LiveScript, and finally renamed to JavaScript. The change of name from LiveScript to JavaScript roughly coincided with Netscape adding support for Java technology in its Netscape Navigator web browser. JavaScript was first introduced and deployed in the Netscape browser version 2.0B3 in December of 1995. When JavaScript was added to Internet Explorer, it had to be officially called "JScript" because Netscape owns the name "JavaScript". The choice of name proved to be a source of much confusion.

As of 2006, the latest version of the language is JavaScript 1.7, which corresponds to ECMA-262 Edition 3 like JavaScript 1.5, except for Array extras, Array and String generics, and pythonic generators and array comprehensions. ECMAScript, in simple terms, is a standardized version of JavaScript. The ECMA-357 standard specifies E4X (ECMAscript For XML), a language extension dealing with XML.

Versions of JavaScript[edit]

JavaScript
Version Description Support
1.0 Netscape 2.0
1.1 Netscape 3.0
1.2 Netscape 4.0-4.05
1.3 Netscape 4.06-4.7x
1.4 Netscape server products
1.5 Netscape 6.0


JScript
Version Description Support
1.0 Internet Explorer 3.0
2.0
3.0 Internet Explorer 4.0
4.0
5.0 Internet Explorer 5.0
5.1 Internet Explorer 5.01
5.5 Internet Explorer 5.5, 6.0


ECMAScript
Version Description Support
v1
v2
v3

ECMAScript[edit]

ECMAScript, also known as ISO standard 16262, is a standardization based on JavaScript by ECMA International, first written in 1996. It defines a dynamically-typed language (derived from C) very loosely based on Java and other C-like languages. It supports some object-oriented features through prototype-based objects and pseudo-classes.

All ECMAScript code should work in all major browsers that support JavaScript, but not necessarily vice versa, as there are many proprietary extensions by Netscape, Microsoft (IE), and Opera.

The latest version is ECMA-262 Edition 3, based on version 1.5 of JavaScript, and the specification is publicly available.

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