ECMAScript history

ECMAScript From the beginning of formulation to the final release , after 15 year . Here is a table to illustrate its development process .

Time	ECMA	JS	remarks
1996.11	ES1.0	JS Stable	Netscape Submit to ECMA organization ,ES Officially
1997 year	ES1.0		ES Official release
1998.06	ES2.0		ES2 Official release
1999.12	ES3.0	Full inheritance of later versions	The industry widely supports . What beginners learn at the beginning Js, In fact, I learned 3.0 The grammar of
2000 year	ES4.0		Start brewing
2007.10	ES4.0		Not through , Because it's too radical , It's abandoned . after 7 year , But failed
2008.07	ES3.1		take ES4 It's about ES3.0 Now part of the functional improvement , Publish into this version , The project code of this version is Harmony( harmonious )
2009.12	ES5.0	Basically compatible ES3.1	ES5.0 Official release .ES5 a ES3 Basically nothing changed . At the same time JavaScript.next, Later, ES6.
2011.06	ES5.1		ES5.1 Become ISO international standard
2013.03	ES6.0		Final draft
2013.12	ES6.0		Draft release
2015.06	ES6.0		Official release .

The following is a textual description of the previous paragraph ：
ECMAScript 1.0 yes 1997 Published in , The next two years , Released continuously ECMAScript 2.0（1998 year 6 month ） and ECMAScript 3.0（1999 year 12 month ）.3.0 Version is a huge success , Widely supported in the industry , Become the standard of passage , Laid down JavaScript The basic grammar of language , Later versions inherit completely . Until today, , Beginners start learning JavaScript, It's just learning 3.0 Version of the grammar .

2000 year ,ECMAScript 4.0 Start brewing . This version didn't pass at last , But most of it is ES6 Inherited . therefore ,ES6 The starting point is actually 2000 year .

Why? ES4 Didn't pass ？ Because this version is too radical , Yes ES3 Made a complete upgrade , This has led some members of the standards committee to be reluctant to accept .ECMA Of the 39 Technical Expert Committee No （Technical Committee 39, abbreviation TC39） Be responsible for making ECMAScript standard , Members include Microsoft、Mozilla、Google Wait for big companies .

2007 year 10 month ,ECMAScript 4.0 Release of draft Edition , It was expected that the next year 8 The official version will be released in May . however , The parties are concerned about whether to adopt this standard , There are serious differences . With Yahoo、Microsoft、Google The leading big company , against JavaScript A major upgrade of , Advocate minor changes ; With JavaScript The creator Brendan Eich Headed by Mozilla company , Stick to the current draft .

2008 year 7 month , Because what features should be included for the next release , There are too many differences between the parties , The argument is too heated ,ECMA The meeting decided , suspend ECMAScript 4.0 Development of , It will involve a small part of the improvement of existing functions , Posted as ECMAScript 3.1, And expand other radical ideas , Put it in a later version , Because of the atmosphere of the meeting , The project code name of this version is Harmony（ harmonious ）. Shortly after the meeting ,ECMAScript 3.1 Just change the name to ECMAScript 5.

2009 year 12 month ,ECMAScript 5.0 Version is officially released .Harmony The project is split in two , Some of the more feasible ideas are named JavaScript.next Continue to develop , Later it evolved into ECMAScript 6; Some not very mature ideas , Is regarded as JavaScript.next.next, Consider launching in the future .TC39 The overall consideration of the committee is ,ES5 And ES3 Basically compatible , Major grammatical modifications and new features are added , Will be made by JavaScript.next complete . at that time ,JavaScript.next refer to ES6, After the release of the Sixth Edition , It means ES7.TC39 Our judgment is ,ES5 Will be in 2013 In the middle of the year JavaScript Mainstream standards for development , And has been in this position for the next five years .

2011 year 6 month ,ECMAScript 5.1 The release of , And become ISO international standard （ISO/IEC 16262:2011）.

2013 year 3 month ,ECMAScript 6 Draft freeze , No more new features . The new functional idea will be put into ECMAScript 7.

2013 year 12 month ,ECMAScript 6 Draft release . And then there was 12 Months of discussion , Listen to feedback from all parties .

2015 year 6 month ,ECMAScript 6 Officially passed , Become an international standard . from 2000 Year counting , Now it's over 15 year .

ES6 And ECMAScript 2015 The relationship between

ECMAScript 2015（ abbreviation ES2015） The word , It's also a common sight . It is associated with ES6 What is the relationship ？

2011 year ,ECMAScript 5.1 After the release , We started to make 6.0 It's published . therefore ,ES6 The original meaning of the word , Is refers to JavaScript The next version of the language .

however , Because this version introduces too many grammatical functions , And in the process of formulation , There are also many organizations and individuals that constantly submit new features . It soon became clear , It's impossible to include all the features that will be introduced in a single version . The usual practice is to release 6.0 edition , I'll send it again after a while 6.1 edition , And then there was 6.2 edition 、6.3 Version and so on .

however , Standard makers don't want to do this . They want to make standard upgrades routine ： Anyone at any time , Can submit a proposal for a new grammar to the Standards Committee , Then the standards committee meets once a month , Assess whether these proposals are acceptable , What improvements are needed . If after many meetings , A proposal is mature enough , You can officially enter the standard . That is to say , Standard version upgrades become a rolling process , It changes every month .

The standards committee finally decided , The standard is at 6 It's officially released in January , As the official version of that year . Next time , It's based on this version , Until the next year 6 month , The draft naturally becomes the new year's version . thus , You don't need the previous version number , Just mark it with the year .

ES6 The first version of , That's it 2015 year 6 Month issued , The official name is 《ECMAScript 2015 standard 》（ abbreviation ES2015）.2016 year 6 month , Slightly revised 《ECMAScript 2016 standard 》（ abbreviation ES2016） Release as scheduled , This version can be seen as ES6.1 edition , Because the difference between the two is very small （ Only the array instance is added includes Methods and exponential operators ）, It's basically the same standard . According to the plan ,2017 year 6 Published in ES2017 standard .

therefore ,ES6 It's a noun , It is also a general reference to , The meaning is 5.1 Version later JavaScript The next generation of standards , covers ES2015、ES2016、ES2017 wait , and ES2015 It's the official name , It refers to the official version of the language standard issued in that year . It is mentioned in this book that ES6 The place of , Generally speaking, it means ES2015 standard , But sometimes it also refers to “ The next generation JavaScript Language ”.

in summary （ Personal understanding ）：
In the future , No longer officially named ES7,ES8,… wait , Because in ES6 After the version, the version will no longer be named by the version number ; Of course, you can still call it that .
There will only be ES6, Use ES6 To refer to ES2015 And later updates .
And why is it called ES6 Well , instead of ES7,ES8 Well ？ Mainly because , It is ES5.1 Next version of .
and ES2015 It is ES6 The first version of . Most of the time , You can take ES2015 and ES6 As a thing

Reference resources ： Ruan Yifeng's 《ECMAScript6 introduction 》