The Fetch API provides an interface for fetching resources (including across the network). It will seem familiar to anyone who has used XMLHttpRequest, but the new API provides a more powerful and flexible feature set.

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The fetch() method takes one mandatory argument, the path to the resource you want to fetch. It returns a Promise that resolves to the Response to that request — as soon as the server responds with headers — even if the server response is an HTTP error status. You can also optionally pass in an init options object as the second argument (see Request).

Once a Response is retrieved, there are a number of methods available to define what the body content is and how it should be handled.

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