ECMA-262 is the official name of the standard. ECMAScript is the official name of the language.
|1997||ECMAScript 1||First Edition.|
|1998||ECMAScript 2||Editorial changes only.|
|1999||ECMAScript 3||Added Regular Expressions.
|ECMAScript 4||Was never released.|
|2009||ECMAScript 5||Added “strict mode”.
Added JSON support.
|2011||ECMAScript 5.1||Editorial changes.|
|2015||ECMAScript 6||Added classes and modules.|
|2016||ECMAScript 7||Added exponential operator (**).
ECMAScript 6 is also called ECMAScript 2015.
ECMAScript 7 is also called ECMAScript 2016.
ECMAScript 3 is fully supported in all browsers.
ECMAScript 5 is fully supported in all modern browsers*.
ECMAScript 6 is partially supported in all modern browsers.
ECMAScript 7 is poorly supported in all browsers.
* Internet Explorer 9 does not support ECMAScript 5 “use strict”.
ECMAScript Browser Implementations
|V8||6||Chrome (Partial Support)|
|SpiderMonkey||6||Firefox (Partial Support)|
|Chakra||6||Edge (Partial Support)|
|Nitro||6||Safari (Partial Support)|
|V8||6||Opera (Partial Support)|
This list compares the version numbers of the three different products:
|1996||1.0||Internet Explorer 3|
|1997||1||3.0||Internet Explorer 4|
|1999||2||5.0||Internet Explorer 5|
|1999||2||5.1||Internet Explorer 5.1|
|2000||3||5.5||Internet Explorer 5.5|
|2001||3||5.6||Internet Explorer 6|
|2006||3||5.7||Internet Explorer 7|
|2009||3||5.8||Internet Explorer 8|
|2009||1.8.1||5||Firefox 3.5 (Partial Support)|
|2009||1.8.2||5||Firefox 3.6 (Partial Support)|
|2011||5||9.0||Internet Explorer 9 (Partial Support)|
Internet Explorer 5 (JScript 5.0) was the first browser to support ECMAScript 2.