ES6 (ECMAScript 6) 101

Many companies start to use ES6 to write Javascript codes and use transpilation tool to transform ES6 codes to well-supported ES5 codes.

Here are some concepts (new stuff) in ES6

• Variables (let, const)
• Arrow Functions (map, set, =>)
• Strings (startsWith, endsWith, includes, repeat)
• TEMPLATE LITERAL (${name})
• Arrays (Array.from, Array.of, find, findIndex, fill)
• Math (Math.sign, Math.trunc, Math.cbrt)
• Spread Operator (...)
• Destructuring (let [x, y] = [1, 2];)
• Parameters (function(defaultX = 1), REST PARAMETERS ...remaining)
• Modules (export function/var, import from, export default)
• Classes (class, constructor, extends, new)
• Symbols (getOwnPropertySymbols)
• Transpilation (Babel, Traceur, TypeScript, ScratchJS)

https://kangax.github.io/compat-table/es6/ has the complete list and cross browser support status, and some other concepts are not covered above like

• Proxy
• Promise
• Reflect
• RegExp y and u flags