1995

• Brendan Eich developed JavaScript for Netscape.

1996

• Microsoft developed JScript.
• Netscape transferred control of the JavaScript standard to ECMA, but retained the trademark; hence, ECMAScript.

1997

• Microsoft introduced DHTML.

1998

• W3C published the DOM standard.
• Mozilla founded.

1999

• Microsoft implemented XMLHttpRequest.
• ECMA published the ES3 spec.
  • Regular expressions
  • try/catch
  • switch
  • Strict equality operators (=== and !==)
  • do...while
  • Unicode format-control characters
  • Error objects
  • encodeURI/decodeURI
  • instanceof
  • in

2002

• Douglas Crockford introduced JSON and JSLint
• Oddpost developed the first Ajax application.

2004

• WHATWG founded.
• Apple introduced the canvas element.

2005

• Jesse James Garrett coined the term Ajax.

2006

• John Resig released jQuery.
• Joe Hewitt released Firebug.
• Yahoo released YUI.

2008

• Google released the first modern JavaScript engine, V8, with JIT compilation for Chrome.
• Apple added Web SQL to their Safari browser.
• ECMA abandoned the proposed ES4 and EX4 standards.

2009

• Ryan Dahl developed Node.
• Isaac Z. Schlueter developed npm.
• Kevin Dangoor introduced CommonJS.
• Nitobi Software developed Cordova (née PhoneGap).
• Jeremy Ashkenas released underscore.js.
• Arun Ranganathan wrote the first File API spec at Mozilla.
• ES5
  • "use strict"
  • Array methods
  • Object methods
  • JSON
  • bind
  • Date.now/valueOf
  • String.trim

2010

• Google released Angular.
• Jeremy Ashkenas released backbone.js and Coffeescript.
• Nikunj Mehta designed IndexedDB at Oracle.

2011

• Mozilla announced WebAPIs
• The Khronos Group announced WebGL along with Typed Arrays.
• TJ Holowaychuk developed Express
• Yehuda Katz developed Ember
• James Halliday developed Browserify

2012

• Microsoft released TypeScript and WinJS
• John-David Dalton developed Lodash
• Ben Alman developed Grunt

2013

• Facebook released React developed by Jordan Walke.
• Mozilla released asm.js
• Github released Electron.
• Eric Schoffstall developed gulp

2014

• HTML5
• webpack
• Sebastian McKenzie developed Babel
• Guillermo Rauch developed Socket.IO
• Evan You developed Vue
• Matt Zabriskie developed Axios

2015

• Facebook released React Native.
• Dan Abramov and Andrew Clark developed Redux.
• WHATWG introduced the fetch standard.
• Mathias Biilmann coined the term Jamstack
• ES2015 (ES6)
  • let/const
  • Promises
  • Classes
  • Modules
  • Symbols
  • Map
  • Set
  • Rest and Spread operators (...)
  • Arrow functions (=>)
  • Template Literals
  • Object methods
    • is
    • assign
    • setPrototypeOf
  • String.repeat/codePointAt/normalize
  • Array.find and findIndex
  • for-of loops
  • destructuring

2016

• ES2016
  • Array.includes
  • Exponentiation (**)
• Guillermo Rauch released Next.js.
• Storybook was developed by Kadira.

2017

• WebAssembly
• ES2017
  • async/await
  • String.padStart/padEnd
  • Object.entries/values
  • getOwnPropertyDescriptors
  • trailing commas

2018

• React Hooks
  • useState
  • useReducer
  • useEffect
  • useContext
• ES2018
  • Rest/spread for objects
  • for-await-of
  • Promise.finally
  • Regex-
    • Unicode properties
    • Lookbehind
    • Named capture groups
    • Multiline match

2019

• ES2019
  • Array.flat/flatMap
  • String.trimStart/trimEnd
  • Object.fromEntries
  • Function.toString
  • Symbol.description
  • Optional catch binding

2020

• ES2020
  • Dynamic imports
  • BigInt
  • String.matchAll
  • Promise.allSettled
  • Nullish coalescing operator (??)
  • Optional chaining operator (?.)
  • globalThis

2021

• ES2021
  • String.replaceAll
  • Promise.any
  • Logical assignment operators (||=, ??=, &&=)
  • Underscores as commas in integers
  • WeakRef

2022

• ES2022
  • Array.at

2023

• ES2023

2024

• ES2024 (ES15)