It was developed for Netscape 2, and became the ECMA-262 standard in 1997.
Internet Explorer (IE4) was the first browser to support ECMA-262 Edition 1 (ES1).
|1997||ES1||ECMAScript 1 was released|
|1997||ES1||IE 4 was the first browser to support ES1|
|1998||ES2||ECMAScript 2 was released|
|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|
|2008||ES4||ECMAScript 4 was abandoned|
|2009||ES5||ECMAScript 5 was released|
|2011||ES5||IE 9 was the first browser to support ES5 *|
|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
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:
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|