ECMAScript 5 was standardized in December 2009. I first heard and blogged about ECMAScript 6 in January 2011, when it was still called Harmony. The original plan was to finish ES6 in 2013, but things took longer and it was standardized in June 2015. (A more detailed account of ES6’s history is given in the next chapter.)
This book can be read online for free. If you find it useful, please support it by buying a copy. You’ll get DRM-free PDF, EPUB, MOBI files.
I hope that reading the book conveys some of the fun I had investigating and playing with ES6.