Over many years, JavaScript has grown to become probably the most widely used programming language in the world. Nevertheless, the language itself has a few problems that many have attempted to address by using libraries or even by implementing their own languages that run on top of JavaScript (of which we’ve mentioned both CoffeeScript and ClojureScript before). ES6 (aka ECMAScript 6 or ECMAScript 2015), the new version of JavaScript, addresses many of the concerns of the older versions currently in use. Although browser support is scarce, support from mature transpilers like Babel allows you to write ES6 and have it supported in older browsers. For new projects, we strongly suggest starting with ES6 from day one.