Understanding ES6′ Async/Await
The simple example:
(async function() { let a = await fetch('/') console.log(await a.text()) })()
The simple example with a simple explanation:

The simple example again, this time with a in-depth explanation :

There’s much more about async/await but this might be a good start. Even if you don’t know anything about Promises yet, read the example, put the four lines into the browser’s JS console and play around: Leave one or both ‘awaits’ away, read the error messages and you should slowly get a feeling.
Source: https://medium.com/@theden/async-await-simple-example-in-four-lines-of-code-b3bc02c2fa34