Why does Angular build create files with 'es5' and 'es2015' but not 'es6' (or no suffix at all)?

Question

I recently downloaded the Angular CLI (@angular/cli 9.0.1). I then proceeded to create a new application so that I could create a new Angular Element, package it up

Answer 1

ES2015 is the same as ES6. ECMAScript 6 was released in 2015.

Some history:

https://codeburst.io/javascript-wtf-is-es6-es8-es-2017-ecmascript-dca859e4821c