The current version of JavaScript. We support "old" browsers, so we can't use it on the client side*, but we can totally use it server-side or in other environments where we have stricter control over the JS runtime.
ES6 has various new features:
Put it at the top of files to switch on "strict mode" which fixes various behaviours that have led developers over the ages to call JS "broken". For example, some comparisons, especially with NaN
, undefined
, and null
; also disables the performance-hurting with
keyword.