As Angular is maturing, it gets harder and harder for newcomers to make sense of the abundance of materials you find online. I’m pretty sure that at this point, the vast majority of Angular 1.x tutorials use outdated Angular practices–things that modern Angular 1.x projects should not be using.
In this article, we are going to write Angular 2 code in ES5 with the current latest version. As a recap, we know that Angular 2 is written in the TypeScript language, which gives the developers an advantage of various strong features of this language such as types, metadata annotations through decorators, etc. It is true that the developers who are new to TypeScript may find themselves a bit unclear and unskilled with the start-up examples of Angular 2 which are written in the TypeScript language along with the constructs such as classes in ECMAScript 6. To make it easier and more understandable, experienced developers figured out a way to write Angular 2 code in ES5, instead of TypeScript or ES6.