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JavaScript. W3Schools in English. Lessons for beginners


JavaScript History

JavaScript / ECMAScript

JavaScript was invented by Brendan Eich in 1995.

It was developed for Netscape 2, and became the ECMA-262 standard in 1997.

After Netscape handed JavaScript over to ECMA, the Mozilla foundation continued to develop JavaScript for the Firefox browser. Mozilla's latest version was 1.8.5. (Identical to ES5).

Internet Explorer (IE4) was the first browser to support ECMA-262 Edition 1 (ES1).

Year ECMABrowser
1995   JavaScript was invented by Brendan Eich
1996   Netscape 2 was released with JavaScript 1.0
1997   JavaScript became an ECMA standard (ECMA-262)
1997 ES1 ECMAScript 1 was released
1997 ES1 IE 4 was the first browser to support ES1
1998 ES2 ECMAScript 2 was released
1998   Netscape 42 was released with JavaScript 1.3
1999 ES2 IE 5 was the first browser to support ES2
1999 ES3 ECMAScript 3 was released
2000 ES3 IE 5.5 was the first browser to support ES3
2000   Netscape 62 was released with JavaScript 1.5
2000   Firefox 1 was released with JavaScript 1.5
2008 ES4 ECMAScript 4 was abandoned
2009 ES5 ECMAScript 5 was released
2011 ES5 IE 9 was the first browser to support ES5 *
2011 ES5 Firefox 4 was released with JavaScript 1.8.5
2012 ES5 Full support for ES5 in Safari 6
2012 ES5 Full support for ES5 in IE 10
2012 ES5 Full support for ES5 in Chrome 23
2013 ES5 Full support for ES5 in Firefox 21
2013 ES5 Full support for ES5 in Opera 15
2014 ES5 Full support for ES5 in all browsers
2015 ES6 ECMAScript 6 was released
2016 ES6 Full support for ES6 in Chrome 51
2016 ES6 Full support for ES6 in Opera 38
2016 ES6 Full support for ES6 in Edge 14
2016 ES6 Full support for ES6 in Safari 10
2015 ES6 Full support for ES6 in Firefox 52
2018 ES6 Full support for ES6 in all browsers **


* Internet Explorer 9 did not support ES5 "use strict".

** Internet Explorer 11 does not support ES6.

The ECMA Technical Committee 39

In 1996, Netscape and Brendan Eich took JavaScript to the ECMA international standards organization, and a technical committee (TC39) was created to develop the language.

ECMA-262 Edition 1 was released in June 1997.

From ES4 to ES6

When the TC39 committee got together in Oslo in 2008, to agree on ECMAScript 4, they were divided into 2 very different camps:

The ECMAScript 3.1 Camp:
Microsoft and Yahoo who wanted an incremental upgrade from ES3.

The ECMAScript 4 Camp:
Adobe, Mozilla, Opera, and Google who wanted a massive ES4 upgrade.

August 13 2008, Brendan Eich wrote an email:

It's no secret that the JavaScript standards body, Ecma's Technical Committee 39, has been split for over a year, with some members favoring ES4, a major fourth edition to ECMA-262, and others advocating ES3.1 based on the existing ECMA-262 Edition 3 (ES3) specification. Now, I'm happy to report, the split is over.

The solution was to work together:

  • ECMAScript 4 was renamed to ES5
  • ES5 should be an incremental upgrade of ECMAScript 3.
  • Features of ECMAScript 4 should be picked up in later versions.
  • TC39 should develop a new major release, bigger in scope than ES5.

The planned new release (ES6) was codenamed "Harmony" (Because of the split it created?).

ES5 was a huge success. It was released in 2009, and all major browsers (including Internet Explorer) were fully compliant by July 2013:

Chrome 23 IE10 / Edge Firefox 21 Safari 6 Opera 15
Nov 2012 Sep 2012 May 2013 Jul 2012 Jul 2013

ES6 was also a huge success. It was released in 2015, and all major browsers were fully compliant by March 2017:

Chrome 51 Edge 14 Firefox 52 Safari 10 Opera 38
May 2016 Aug 2016 Mar 2017 Sep 2016 Jun 2016