I have worked with Angular 1.x and now starting with Angular 2. Now I am overwhelmed to see the number of js scripts that we have to add to our index.html just to get started.

I mean even if I exclude angular's (and its components') own js files, there are `"systemjs"`, `"es6-shim"`, `"reflect-metadata"`, `"rxjs"`, `"zone.js"`.

And I keep on hearing that Angular 2 is 2 to 3 times faster than Angular 1.

I have used AngularJS 1.x and also ReactJS and no where I have seen this much dependency on other scripts.

What I don't understand is this - *Don't all these script files make the browsers slow? Don't they create extra load on the JS Engine of the browser?* 

And are we assuming that we are only targeting the latest of browsers when we are developing in angular 2 ?

Will anyone please explain?

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**EDIT:**

I would like to understand the performance effect by lots of JavaScript files.

Can you refuse/reject the fact that Angular 2 needs a lot more JS files to start working than Angular 1?