Javascript versions

JavaScript was first released in 1995 and confirms to ECMAScript (ES) specification. ECMAScript version 1 was released in 1997 and since then there have been lot of revisions as mentioned below.

ES5 features - 2009

Here is the list of features added in ES5.

• use strict directive - declare variables explicitly
• String.trim() method added - used to remove white spaces from both ends of String
• String.charAt() method added - used to get character at specific position in String
• Lot of methods added to Array - isArray, foreach, map, filter, reduce, every sum, indexof, lastindexof
• JSON object new methods - parse, stringify
• Date.now() method added
• Object related changes - getters and setters, adding new property to objects
• Access String property using []
• support for multiline string literals

ES6 features - 2015

Here is the list of features added in ES6.

• let
• const
• Promises
• ES6 modules - import and export syntax
• Arrow function - similar to lambda in Java
• Class syntax
• Template literals
• for ... of loop
• Default parameters
• New Array methods - find() and findIndex()
• New Number methods - isFinite() and isNaN()
• map, set, weakmap, weakset
• Binary data
• Typed Arrays
• Iterators

ES7 features - 2016

Here is the list of features added in ES7.

• Array.prototype.includes
• Exponentiation - ** - similar to Math.Pow
• Destructuring
• async .. await

ES8 - 2017

• Object.values, Object.entries and Object.getOwnPropertyDescriptors
• Concurrency and atomics features
• asyn ...await improvements

ES9 - 2018

• spread operator and rest parameters - ...
• Promise.prototype.finally

ES10 - 2019

• Array.prototype.flat, Array.prototype.flatMap, Improvements in Array.sort and Object.fromEntries
• Catch binding is optional

ES11 - 2020

• BigInt - supports number larger than Number.MAX_SAFE_INTEGER
• ?? - nullish coalescing operator - returns right hand side operand when left hand side operand is null or undefined. For false and NaN, it returns false and NaN itself unlike || operator.
• globalThis object
• optional chaining - ?.

ES12 - 2021

• replaceAll method for strings
• Promise.any
• AggregateError
• ??=, ||=
• garbage collection improvements
• Array.prototype.sort improvements

ES13 - 2022

• Regular expression indexing improvements
• at() method for indexable object
• top level await
• error.cause

ES.Next

• Array.prototype.findLast() and Array.prototype.findLastIndex()