JavaScript Versions
JavaScript was invented by Brendan Eich in 1995, and
became an ECMA standard
in 1997.
ECMA-262 is the official name of the standard. ECMAScript is the official name of the language.
ECMAScript Editions
| Year | Name | Description |
|---|---|---|
| 1997 | ECMAScript 1 | First Edition. |
| 1998 | ECMAScript 2 | Editorial changes only. |
| 1999 | ECMAScript 3 | Added Regular Expressions. Added try/catch. |
| 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 (**). Added Array.prototype.includes. |
ECMAScript 6 is also called ECMAScript 2015.
ECMAScript 7 is also called ECMAScript 2016.
Browser Support
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
| Engine | ECMA | Browser |
|---|---|---|
| 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) |
| V8 | 5 | Chrome 23 |
| SpiderMonkey | 5 | Firefox 21 |
| JavaScript 1.8.5 | 5 | Firefox 4 |
| Nitro | 5 | Safari 6 |
| V8 | 5 | Opera 15 |
| Chakra | 5 | Edge 12 |
| Chakra | 5 | IE 10 |
JavaScript / ECMAScript / JScript
JavaScript was developed for Netscape. The first browser to run JavaScript was Netscape 2 in 1996. After Netscape the Mozilla foundation continued to develop JavaScript for the Firefox browser. JavaScript version numbers run from 1.0 to 1.8.
ECMAScript was developed by Ecma International after the organization adopted JavaScript. The first edition of ECMAScript was released in 1997. ECMAScript version numbers run from 1 to 7.
JScript was developed by Microsoft as a compatible JavaScript language for Internet Explorer in 1996. JScript version numbers runs from 1.0 to 9.0.
This list compares the version numbers of the three different products:
| Year | JavaScript | ECMA | JScript | Browser |
|---|---|---|---|---|
| 1996 | 1.0 | Netscape 2 | ||
| 1996 | 1.0 | Internet Explorer 3 | ||
| 1996 | 1.1 | Netscape 3 | ||
| 1997 | 1.2 | Netscape 4 | ||
| 1997 | 1 | 3.0 | Internet Explorer 4 | |
| 1998 | 1.3 | 1 | Netscape 4.06 | |
| 1999 | 2 | 5.0 | Internet Explorer 5 | |
| 1999 | 2 | 5.1 | Internet Explorer 5.1 | |
| 2000 | 3 | 5.5 | Internet Explorer 5.5 | |
| 2000 | 1.5 | 3 | Netscape 6 | |
| 2000 | 1.5 | 3 | Firefox 1 | |
| 2001 | 3 | 5.6 | Internet Explorer 6 | |
| 2006 | 3 | 5.7 | Internet Explorer 7 | |
| 2005 | 1.6 | 3 | Firefox 1.5 | |
| 2006 | 1.7 | 3 | Firefox 2 | |
| 2008 | 1.8 | 3 | Firefox 3 | |
| 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 | 1.8.5 | 5 | Firefox 4 | |
| 2011 | 5 | 9.0 | Internet Explorer 9 (Partial Support) |
Internet Explorer 4 (JScript 3.0) and Netscape 4.06 (JavaScript 1.3) were the first browsers to support ECMAScript 1.
Internet Explorer 5 (JScript 5.0) was the first browser to support ECMAScript 2.
Internet Explorer 5.5 (JScript 5.5) and Netscape 6 (JavaScript 1.5) were the first browsers to support ECMAScript 3.
Internet Explorer 9 (JScript 9.0) and Firefox 3.5 (JavaScript 1.8.1) were the first browsers to support ECMAScript 5.
