In this course module, you've got an overview over the API and the promise API, two super important API
you have to know when working with service workers and with progressive web apps in general. You will
notice that throughout this course, we use promises all over the place,
therefore this then call and catch call has to be something you immediately recognize and you understand
where it's coming from and what it does,
that was the goal of this module.
You'll also see that we do quite a lot of fetch requests,
we'll even use fetch in the service worker,
actually we already do so as you learned
and it's important to understand for you too, what does fetch actually do?
It sends a HTTP request,
that's the core of it.
Now if that you're well prepared and we can now go back to the progressive web app and dive much deeper
into service workers.